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Classification of Plants Class 9 Science Chapter 6 Questions And Answers Maharashtra Board

January 6, 2025January 5, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Science Solutions Chapter 6 Classification of Plants Notes, Textbook Exercise Important Questions and Answers.

Std 9 Science Chapter 6 Classification of Plants Question Answer Maharashtra Board

Class 9 Science Chapter 6 Classification of Plants Question Answer Maharashtra Board

1. Match the proper terms from columns A and C with the description in column B.

2. Complete the sentences by filling in the blanks and explain those statements.
(angiosperms, gymnosperms, spore, Bryophyta, thallophyta, zygote)
a. ……………….. plants have soft and fiber-like body.

b. ……………….. is called the ‘amphibian’ of the plant kingdom.
Answer:
Bryophyta plant is called the ‘amphibian’ of the plant kingdom

c. In pteridophytes, asexual reproduction occurs by ……………….. formation and sexual reproduction occurs by ………………..formation.
Answer:
Spore, zygote: Pteridophyta plants show alteration of generation. One generation reproduces by spore-formation and the next generation reproduces sexually by zygote formation.

d. Male and female flowers of ……………….. are borne on different sporophylls of the same plant.
Answer:
Gymnosperms bear their male and female flowers on different sporophylls of the same plant

3. Answer the following questions in your own words.

a. Write the characteristics of subkingdom Phanerogams.
Answer:

Plants which have special structures for reproduction and produce seeds are called Phanerogams.
In these plants, after the process of reproduction, seeds are formed which contain the embryo and stored food.
During the germination of the seed, the stored food is used for the initial growth of the embryo.
Depending upon whether seeds are enclosed in a fruit or not phanerogams are classified into gymnosperms and angiosperms.

b. Distinguish between monocots and dicots.
Answer:

	Dicots	Monocots
Seed	Two cotyledons	Single cotyledon
Root	Well developed, primary root (Taproot)	Fibrous roots
Stem	Strong, hard. e.g. Banyan tree	Hollow, e.g. Bamboo False, e.g. Banana Disc-like, e.g. Onion.
Leaf	Reticulate venation	Parallel venation
Flower	Flowers with 4 or 5 parts or in their multiples (tetramerous or pentamerous)	Flowers with 3 parts or in multiples of three (trimerous).

c. Write a paragraph in your own words about the ornamental plants called ferns.
Answer:

Ferns belong to the group of plants called Pteridophyta.
They have well-developed roots, stem and leaves but do not bear flowers and fruits.
They have separate tissues for the conduction of food and water.
They reproduce with the help of spores formed along the back or posterior surface of their leaves.
They reproduce asexually by spore formation and sexually by zygote formation.

d. Sketch, label and describe the Spirogyra.

e. Write the characteristics of the plants belonging to division Bryophyta.
Answer:

Bryophyta group of plants are called the amphibians of the plant kingdom because they grow in moist soil but need water for reproduction.
These plants are thalloid, multicellular and autotrophic.
They reproduce by spore-formation.
Their plant body structure is flat, ribbon-like, long, without true roots, stem and leaves.
Instead, they have stem-like or leaf-like parts and root-like rhizoids.
They do not have specific tissues for the conduction of food and water.
Examples: Moss (Funaria), Anthoceros, Riccia etc.?

4. Sketch and label the figures of the following plants and explain them into brief.
Marchantia, Funaria, Fern, Spirogyra.

Question 1.
Spirogyra.
Answer:

Spirogyra belongs to the division thallophyta. They are called as algae.
It grows mainly in water.
It does not have specific parts like root-stem- leaves-flowers but are autotrophic due to the presence of chlorophyll.
The plant body of Spirogyra is soft and fibre-like.
It has spirally arranged chloroplasts in its cell.

Question 2.
Funaria and Marchantia (Bryophyta)
Answer:

These plants are called ‘amphibians’ of the plant kingdom because they grow mostly in soil and need water for reproduction.
They do not have specific tissues for the conduction of food and water.
The plant body is fiat, ribbon-like long, without true roots, stem and leaves
Instead, they have stem-like or leaf-like parts and root like rhizoids.

Question 3.
Fern (Pteridophyta):
Answer:

They have well-developed roots, stem and leaves for the conduction of food and water.
They do not bear flowers and fruits.
They reproduce with the help of spores present along the back or posterior surface of the leaves.

5. Collect a monocot and dicot plant available in your area. Observe the plants carefully and describe them in scientific language.

6. Which criteria are used for the classification of plants? Explain with reasons.
Answer:
Criteria for classification of plants:

If plants do not bear flowers, fruits and seeds, they are non-seed bearing plants. If they bear flowers, fruit and seeds, they are seed-bearing plants.
Presence or absence of conducting tissues- Plants such as pteridophytes, gymnosperms and angiosperms which possess conducting tissues are included in vascular plants whereas thallophytes and bryophytes which do not possess conducting tissues are included under non-vascular plants.
Depending upon whether the seeds are enclosed in fruit or not, plants are classified as gymnosperms (naked-seeds) and angiosperms (seeds covered by fruit)
Depending upon the number of cotyledons in seeds, plants are classified into dicotyledons and monocotyledons

Class 9 Science Chapter 6 Classification of Plants Intext Questions and Answers

Can you recall?

Question 1.
How have living organisms been classified?
Answer:
(i) Organisms have been classified based on the following:

Cell structure
Body Organisation
Mode of nutrition
Reproduction

(ii) Organisms are also classified at kingdom level and groups and subgroups.

Activity-based questions

Question 1.
You may have seen a lush green soft carpet on old walls, bricks and rocks in the rainy season. Scrape it gently with a small ruler, observe it under a magnifying lens and discuss.
Answer:

It shows considerable tissue complexity and is differentiated into two main parts: a root and a shoot.
They have a variety of specialized tissues within these two regions of the body.
Same kind of cells are seen throughout the whole body except reproductive cells.

Question 2.
You may have seen ferns among the ornamental plants in a garden. Take a leaf of a fully grown fern and observe it carefully.
Answer:

New leaves typically expand by the unrolling in a tight spiral manner.
The anatomy of fern leaves can either be simple or highly divided.
They show the presence of spores formed along the back or posterior surface of their leaves.

Question 3.
Observe all garden plants like Cycas, Christmas tree, Hibiscus, Lily, etc. and compare them. Note the similarities and differences among them. Which differences did you notice in gymnosperms and angiosperms?
Answer:
Cycas and Christmas tree are gymnosperms, whereas Hibiscus and lily are angiosperms.

Similarities: These plants have special structures for reproduction and produce seeds. During the germination of the seed, the stored food is used for the initial growth of the embryo.
Differences: In gymnosperms, reproductive organs have cones whereas in angiosperms reproductive organs have flowers.
In gymnosperms, seeds are without natural coverings whereas in angiosperms seeds are enclosed in natural coverings called fruits.

Question 4.
Soak the seeds of corns, beans, groundnut, tamarind, mango, wheat, etc. in water for 8 to 10 hrs. After they are soaked, check each seed to see whether it divides into two equal halves or not and categorize them accordingly.
Answer:
Monocots: com, wheat (it cannot be divided into equal halves)
Dicots: beans, groundnut, tamarind and mango (it can be divided into two equal halves)

Class 9 Science Chapter 6 Classification of Plants Additional Important Questions and Answers

Choose and write the correct option:

Question 1.
The five-kingdom classification was proposed b7
(a) Robert Whittaker
(b) Robert Hooke
(c) Eichler
(d) Louis Pasteur
Answer:
(a) Robert Whittaker

Question 2.
In 1883, classified plants into two sub-kingdoms.
(a) Robert Whittaker
(b) Alexander Fleming
(c) Eichler
(d) Robert Hooke
Answer:
(c) Eichler

Question 3.
Ulothrix, ulva, sargassum belong to
(a) Bryophyta
(b) Thallophyta
(c) Pteridophyta
(d) Gymnosperms
Answer:
(b) Thallophyta

Question 4.
is a bryophyte.
(a) Ulva
(b) Nephrolepis
(c) Funaria
(d) Equisetum
Answer:
(c) Funaria

Question 5.
In the seeds are naked.
(a) Pteridophyta
(b) Angiosperms
(c) Gymnosperms
(d) Bryophyta
Answer:
(c) Gymnosperms

Question 6.
In the flowers are reproductive organs.
(a) Angiosperms
(b) Gymnosperms
(c) Pteridophyta
(d) Bryophyta
Answer:
(a) Angiosperms

Question 7.
In the flowers are tetramerous or pentamerous.
(a) Monocotyledons
(b) Dicotyledons
(c) Gymnosperms
(d) Pteridophyta
Answer:
(b) Dicotyledons

Question 8.
In monocotyledonous plants, the stem is
(a) hollow
(b) false
(c) disc-like
(d) all of these.
Answer:
(d) all of these

Question 9.
Lycopodium belongs to
(a) Thallophyta
(b) Bryophyta
(c) Gymnosperms
(d) Pteridophyta
Answer:
(d) Pteridophyta

Question 10.
Leaves of show reticulate venation.
(a) Bamboo
(b) Banana
(c) Onion
(d) Banyan
Answer:
(d) Banyan

Question 11.
Various types of fungi like yeasts and moulds are included in the group
(a) Thallophyta
(b) Halophyte
(c) Xenophyta
(d) Angiosperms
Answer:
(a) Thallophyta

Question 12.
Bryophytes have a root-like structure called
(a) Nodes
(b) Rhizoids
(c) Nodules
(d) Aerenchyma
Answer:
(b) Rhizoids

Question 13.
reproduce with the help of spores formed along the back or posterior surface of their leaves.
(a) Halophyta
(b) Pteridophyta
(c) Thallophyta
(d) Angiosperms
Answer:
(b) Pteridophyta

Question 14.
In ……………………….., the reproductive organs cannot be seen.
(a) Pteridophyta
(b) Cryptogams
(c) Thallophyta
(d) Angiosperms
Answer:
(b) Cryptogams

Question 15.
are mostly evergreen, perennial and woody.
(a) Pteridophyta
(b) Thallophyta
(c) Gymnosperms
(d) Angiosperms
Answer:
(c) Gymnosperms

Question 16.
Gymnosperms bear male and female flowers on different of the same plant.
(a) Branches
(b) Roots
(c) Sporophylls
(d) Flowers
Answer:
(c) Sporophylls

Question 17.
In the seeds are not enclosed by fruit.
(a) Pteridophyta
(b) Thallophyta
(c) Gymnosperms
(d) Angiosperms
Answer:
(c) Gymnosperms

Question 18.
In the seeds are enclosed by fruit.
(a) Pteridophyta
(b) Thallophyta
(c) Gymnosperms
(d) Angiosperms
Answer:
(d) Angiosperms

Question 19.
The plants whose seeds cannot be divided into equal parts are called
(a) Algae
(b) Fungus
(c) Dicotyledons
(d) Monocotyledons
Answer:
(d) Monocotyledons

Question 20
The plants whose seeds can be divided into equal parts are called
(a) Algae
(b) Fungus
(c) Dicotyledons
(d) Monocotyledons
Answer:
(c) Dicotyledons

Find the odd one out:

Question 1.
Ulothrix, Ulva, Nephrolepis, Sargassum
Answer:
Nephrolepis: It belongs to division Pteridophyta whereas the others belong to division thallophyta.

Question 2.
Funaria, Marchantia, Anthoceros, Spirogyra
Answer:
Spirogyra:

Question 3.
Marsilea, Pteris, Lycopodium, Riccia
Answer:
Riccia:

Question 4.
Cycas, Mango, Apple, Banyan
Answer:
Cycas:

Question 5.
Onion, Papaya, Wheat, Green peas
Answer:
Green peas:

Complete the analogy:

(1) Spirogyra : Thallophyta : : Riccia :
(2) Moss : Bryophyta : : Selaginella :
(3) Nephrolepis : Pteridophyta :: Ulothrix :
(4) Pteridophyta : Roots :: Bryophyta :
(5) Gymnosperms : naked seeds : : Angiosperms :
(6) Dicotyledon : Reticulate venation : : Monocotyledon:
(7) Bamboo stem: Hollow:: Onion Stem:
(8) Monocotylendon : Tap root:: Dicotyledon :
Answer:
(1) Bryophyta
(2) Pteridophyta
(3) Thallophyta
(4) Rhizoids
(5) Covered seeds
(6) Parallel venation
(7) Disc like
(8) Fibrous roots

Difference between:

Question 1.
Thallophyta and Bryophyta
Answer:

Thallophyta	Bryophyta
These plants grow mainly in water	They grow in moist soil but need water for reproduction

Question 2.
Gymnosperms and Angiosperms
Answer:

Gymnosperms	Angiosperms
No natural covering on seeds	Seeds are formed in fruits

Question 3.
Algae and Moss
Answer:

Algae	Moss
These plants mainly grow in water.	These plants need water for reproduction.

State whether the following statements are true or false. Correct the false statements:

(1) Thallophyta are called as the amphibians of the plant kingdom.
(2) Fungi like yeasts and moulds are included in division bryophyta.
(3) Moss (Funaria) belongs to division bryophyta.
(4) Bryophyta have specific tissues for conduction of food and water.
(5) Plants belonging to Thallophyta group are only unicellular.
(6) Pteridophytes have well developed roots, stems and leaves.
(7) Pteridophytes reproduce with the help of spores formed along the back or posterior surface of their leaves.
(8) Nephrolepis belongs to division Pteridophyta.
(9) Depending upon whether seeds are enclosed in a fruit or not, phanerogams are classified into monocots and dicots.
(10) Gymnosperms are mostly evergreen, perennial and woody.
(11) Gymnosperms bear male and female flowers on different sporophylls of different plants.
(12) In Angiosperms, the seeds are covered by fruits.
(13) Dicotyledonous plants show reticulate venation.
(14) Moncotyledonous plants have trimerous flowers.
(15) In dicotyledonous plants, the stem is strong and hard.
Answer:
(1) False. Thallophyta plants grow mainly in water.
(2) False. Fungi like yeasts and moulds are included in division thallophyta.
(3) True
(4) False. Bryophyta do not have specialised tissuesfor conduction of food and water.
(5) False. Plants belonging to thallophyta group may be unicellular or multicellular.
(6) True
(7) True
(8) True
(9) False. Depending whether seeds are enclosed in. a fruit or not, angiosperms are classified into monocots and dicots.
(10) True
(11) False. Gymnosperms bear male and female flowers on different sporophylls of the same plant.
(12) True
(13) False. Dicotyledonous plants show parallel venation.
(14) True
(15) True.

Give name

Question 1.
What are ornamental plants are called?
Answer:
Ferns

Question 2.
Plants with two cotyledons are called.
Answer:
Dicots

Question 3.
Plants with single cotyledon are called.
Answer:
Monocots

Question 4.
Type of venation showed by hibiscus plant leaves
Answer:
Reticulate venation

Question 5.
Type of venation showed by lily plant leaves
Answer:
Parallel venation

One line answers

Question 1.
Which plants are mostly evergreen, perennial and woody?
Answer:
Gymnosperms are mostly evergreen, perennial and woody.

Question 2.
Which type of venation showed by dicot plants?
Answer:
Leaves of dicot plants show reticulated venation.

Question 3.
Which type of venation showed by monocot plants?
Answer:
Leaves of monocot plants show parallel venation

Question 4.
How are angiosperms classified into monocot and dicot?
Answer:
Depending whether seeds and enclosed in fruit or not, angiosperms are classified into monocot and dicot

Question 5.
In which division are fungi like moulds and yeast classified?
Answer:
Fungi like moulds and yeast classified in division thallophyta.

Question 6.
Plants belonging to which group may be unicellular or multicellular?
Answer:
Plants belonging to thallophyta group may be unicellular or multicellular

Give scientific reason

Question 1.
Thallophyta plants have thin and fibre like body
Answer:
Thallophyta: These plants grow mainly in water i.e. fresh water as well as in saline water, therefore they usually have a soft and fibre-like (filamentous) body.

Question 2.
Bryophyta plants are called the amphibian plants.
Answer:
Bryophyta: They grow in moist soil but need water for reproduction. Therefore, they are called ‘amphibians of plant kingdom’.

Question 3.
Gymnosperms bear their male and female flowers on different sporophylls of the same plant
Answer:
Gymnosperms: As these plants do not take the assistance of pollinators i.e. vectors, the male and female flowers are present on the different sporophyll of the same plant for successful fertilisation.

Write note on

Question 1.
August W. Eichler
Answer:
In 1883, Eichler, a botanist, classified the Kingdom Plantae into two subkingdoms. As a result, two subkingdoms, cryptogams and phanerogams were considered for plant classification.

Question 2.
Thallophyta
Answer:
These plants grow mainly in water. This group of plants, which do not have specific parts like root-stem-leaves-flowers but are autotrophic due to the presence of chlorophyll, is called algae. Algae show great diversity. They may be unicellular or multicellular, and microscopic or large. Examples of algae are Spirogyra, Ulothrix, Ulva, Sargassum, etc. Some of these are found in fresh water while some are found in saline water. These plants usually have a soft and fibre-like body. Various types of fungi like yeasts and moulds which do not have chlorophyll are also included in this group.

Question 3.
Bryophyta
Answer:
This group of plants is called the amphibians’ of the plant kingdom because they grow in moist soil but need water for reproduction. These plants are thalloid, multicellular and autotrophic. They reproduce by spore formation. The structure of the plant body of bryophytes is flat, ribbon-like long, without true roots, stem and leaves. Instead, they have stem-like or leaf-like parts and root-like rhizoids. They do not have specific tissues for conduction of food and water. Examples are Moss (Funaria), Marchantia, Anthoceros, Riccia, etc.

Question 4.
Pteridophyta
Answer:
Plants from this group have well developed roots, stem and leaves and separate tissues for conduction of food and water. But, they do not bear flowers and fruits. They reproduce with the help of spores formed along the back or posterior surface of their leaves. Examples are ferns like Nephrolepis, Marsilea, Pteris, Adiantum, Equisetum, Selaginella, Lycopodium, etc. These plants reproduce asexually by spore-formation and sexually by zygote formation. They have a well-developed conducting system.

Question 5.
Phanerogams
Answer:
Plants which have special structures for reproduction and produce seeds are called phanerogams. In these plants, after the process of reproduction, seeds are formed which contain the embryo and stored food. During germination of the seed, the stored food is used for the initial growth of the embryo. Depending upon whether seeds are enclosed in a fruit or not, phanerogams are classified into gymnosperms and angiosperms.

Question 6.
Gymnosperms
Answer:
Gymnosperms are mostly evergreen, perennial and woody. Their stems are without branches. The leaves form a crown. These plants bear male and female flowers on different sporophylls of the same plant. Seeds of these plants do not have natural coverings, i.e. these plants do not form fruits and are therefore called gymnosperms. (gymnos: naked, sperms: seeds). Examples Cycas, Picea (Christmas tree), Thuja (Morpankhi), Pinus (Deodar), etc.

Question 7.
Angiosperms
Answer:
The flowers these plants bear are their reproductive organs. Flowers develop into fruits and seeds are formed within fruits. Thus, these seeds are covered; hence, they are called angiosperms (angios: cover, sperms: seeds). The plants whose seeds can be divided into two equal halves or dicotyledons are called dicotyledonous plants and those whose seeds cannot be divided into equal parts are called monocotyledonous plants.

Complete the flow chart.

Question 1.
Living Organisms

Answer:

Question 2.
Kingdom: Plantae

Answer:

Distinguish between:

Question 1.
Bryophyta and Pteridophyta:
Answer:

Bryophyta	Pteridophyta
Bryophytes grow in soil but need water for reproduction.	Pteridophytes grow in soil.
Plant body is without specific parts like true roots, stem and leaves.	Plant body is differentiated into true roots, stem and leaves.
Conducting tissues for food and water absent.	Conducting tissues for food and water present.
Examples: Moss (Funaria), Marchantia, Anthoceros, etc.	Examples: Nephrolepis, Marsilea, Pteris, Adiantum, Lycopodium etc.

Question 2.
Angiosperms and Gymnosperms.
Answer:

Angiosperms	Gymnosperms
(i) In Angiosperms, the stems have branches.	(i) In Gymnosperms, the stems are without branches.
(ii) Reproductive organs are flowers.	(ii) Reprodcutive organs are cones.
(iii) Seeds are enclosed in natural coverings, i.e., fruits.	(iii) Seeds are not enclosed in natural coverings.
(iv) Examples: Mango, Bamboo, etc.	(iv) Examples: Cycas, Picea etc.

Question 3.
Cryptogams and Phanerogams.
Answer:

Cryptogams	Phanerogams
(iii) Their reproductive organs are hidden.	(iii) Their reproductive organs are exposed.
(iii) They reproduce by forming spores.	(iii) They reproduce by forming seeds.
(iii) They are less evolved plants.	(iii) They are highly evolved plants.
(iv) They are divided into Thallophyta,	(iv) They are divided into Gymnosperms and
Bryophyta, Pteridophyta.	Angiosperms.

Distinguish between:

Question 1.
Thallophyta
Answer:
Spirogvra, Ulothrix, Ulva, Sargassum

Question 2.
Bryophyta
Answer:
Moss (Funaria), Marchantia, Anthoceros, Riccia

Question 3.
Pteridophyta
Answer:
Nephrolepis, Marsilea, Pteris, Adiantum, Equisetum, Selaginella, Lycopodium

Question 4.
Gymnosperms
Answer:
Cycas, Picca (Christmas tree), Thuja (Morpankhi), Pinus (Deodar)

Question 5.
Angiosperms
Answer:
Tamarind, Mango, Apple, Lemon

Question 6.
Monocot plants
Answer:
Bamboo, bananas, corn, daffodils, garlic, ginger, grass, lilies, onions, orchids, rice, sugarcane, tulips, and wheat

Question 7.
Dicot plants
Answer:
Rose, sunflower, grapes, strawberries, tomatoes, peas, peanuts and potatoes

Observe the figure and answer the questions

1. Dicot Plants

Question 1.
What are the characteristics of the above plants in terms of root system?
Answer:
Well developed, primary root (Tap root)

Question 2.
What are the characteristics of the above plants in terms of flowers?
Answer:
Flowers with 4 or 5 parts or in their multiples (tetramerous or pentamerous)

Question 3.
What are the characteristics of the above plants in terms of leaf venations?
Answer:
Reticulate Venation

Question 4.
What are the characteristics of the above plants in terms of type of stem?
Answer:
Strong and hard

Question 5.
What are the characteristics of the above plants in terms of seed?
Answer:
Two cotyledons

Question 6.
Give example of the following types of plants
Answer:
Rose, sunflower, grapes, strawberries, tomatoes, peas, peanuts and potatoes

2. Monocot Plants

Question 1.
What are the characteristics of the above plants in terms of root system?
Answer:
Fibrous roots

Question 2.
What are the characteristics of the above plants in terms of flowers?
Answer:
Flowers with 3 parts or in multiples of three (trimerous).

Question 3.
What are the characteristics of the above plants in terms of leaf venations?
Answer:
Parallel Venation

Question 4.
What are the characteristics of the above plants in terms of type of stem?
Answer:
Hollow, False or Disc-like

Question 5.
What are the characteristics of the above plants in terms of seed?
Answer:
Single cotyledons

Question 6.
Give example of the following types of plants
Answer:
Bamboo, bananas, com, daffodils, garlic, ginger, grass, lilies, onions, orchids, rice, sugarcane, tulips, and wheat

3. Spirogyra

Question 1.
Which division of plants does this plant come under?
Answer:
This plant come under Division I Thallophyta.

Question 2.
Where does this plant grow?
Answer:
These plants grow mainly in water.

Question 3.
Are these types of plants unicellular or multicellular?
Answer:
They may be unicellular or multicellular and microscopic or large.

Question 4.
Are these types of plant autotropic?
Answer:
They are autotrophic due to the presence of chlorophyll but types of fungi like yeasts and moulds which do not have chlorophyll are also included in this group.

Question 5.
Do these plants have a root-stem-leaves-flowers system?
Answer:
They do not have specific parts like root-stem- leaves-flowers.

Question 6.
How is the body of these types of plants?
Answer:
These plants usually have a soft and fibre-like body.

4. Funaria

Question 1.
Which division of plants does this plant come under?
Answer:
This plant come under Division II Bryophyta.

Question 2.
Where does this plant grow?
Answer:
They grow in moist soil but need water for reproduction.

Question 3.
What are these group of plants called in the plant kingdom?
Answer:
This group of plants is called the ‘amphibians’ of the plant kingdom.

Question 4.
Are these types of plant autotropic?
Answer:
They reproduce by spore formation.

Question 5.
Do these plants have root-stem-leaves-flowers system?
Answer:
The structure of the plant body of bryophytes is flat, ribbon-like long, without true roots, stem and leaves.

Question 6.
What do these plants have instead of roots?
Answer:
They have root like rhizoids.

5. Fern

Question 1.
Which division of plants does this plant come? under?
Answer:
This plant come under Division III Pteridophy ta.

Question 2.
Where does this plant grow?
Answer:
They grow in soil.

Question 3.
How do these plants reproduce?
Answer:
These plants reproduce asexually by spore- formation and sexually by zygote formation.

Question 4.
Do these plants produce flowers and fruits?
Answer:
They do not bear flowers and fruits.

Question 5.
Do these plants have root-stem-leaves-flowers system?
Answer:
Plants from this group have well developed roots, stem and leaves and separate tissues for conduction of food and water.

Question 6.
Where are the spores formed in the plants body?
Answer:
The spores formed along the back or posterior surface of their leaves.

6. Cycas

Question 1.
Which division of plants does this plant come under?
Answer:
This plant come under Division III Phanerogams Division I Gymnosperms.

Question 2.
Explain structure of these types of plants?
Answer:
Gymnosperms are mostly evergreen perennial and woody.

Question 3.
How is stem and leaves of these types of plants?
Answer:
Their stems are without branches and the leaves form a crown.

Question 4.
Where are the male and female flowers located?
Answer:
These plants bear male and female flowers on different sporophylls of the same plant.?

Question 6.
Give some examples of these types of plants?
Answer:
Rose, sunflower, grapes, strawberries, tomatoes, peas, peanuts and potatoes

7. Monocot and Dicot plants

Question 1.
Which division of plants does this plant come under?
Answer:
ThisplantcomeunderDivisionlllPhanerogams Division II Angiosperms

Question 2.
How are the seeds of these types of planis?
Answer:
The seeds are formed within fruits thus these seeds are covered

Question 3.
How can we classify the plants according to their seeds in this division?
Answer:
The plants whose seeds can be divided into two equal halves or dicotyledons are called dicotyledonous plants and those whose seeds cannot be divided into equal parts are called monocotyledonous plants.

Question 4.
How the venations are present on the leaves of these types of plants?
Answer:
These plants bear parallel or reticulated venations on the leaves.

Question 5.
How is the root system of these types of plants?
Answer:
The root systems of these types of plant are tap roots or fibrouš roots.

Complete the paragraph

Question 1.
Thallophyta plants grow mainly in …………….. . This group of plants, which do not have specific parts like root-stem-leaves-flowers but are autotrophic due to the presence of …………….., is called algae. Algae show great diversity. They may be unicellular or …………….., and microscopic or large. Examples of algae are Spirogyra, Ulothrix, Ulva, Sargassum, etc. Some of these are found in fresh water while some are found in saline water. These plants usually have a …………….. and fibre-like body. Various types of …………….. like yeasts and moulds which do not have …………….. are also included in this group.
Answer:
Thallophyta plants grow mainly in water. This group of plants, which do not have specific parts like root-stem-leaves-flowers but are autotrophic due to the presence of chlorophyll, is called algae. Algae show great diversity. They may be unicellular or multicellular, and microscopic or large. Examples of algae are Spirogyra, Ulothrix, Ulva, Sargassum, etc. Some of these are found in fresh water while some are found in saline water. These plants usually have a soft and fibre-like body. Various types of fungi like yeasts and moulds which do not have chlorophyll are also included in this group.

Question 2.
…………….. group of plants is called the amphibians’ of the plant kingdom because they grow in moist soil but need …………….. for reproduction. These plants are thalloid, multicellular and autotrophic. They reproduce by …………….. formation. The structure of the plant body of bryophytes is flat, ribbon?like long, without true …………….., stem and leaves. Instead, they have stem-like or leaf?like parts and root-like ……………. . They do not have specific …………….. for conduction of food and water. Examples are Moss (Funaria), Marchantia, Anthoceros, Riccia, etc.
Answer:
Bryophyta group of plants is called the ‘amphibians’ of the plant kingdom because they grow in moist soil but need water for reproduction. These plants are thalloid, multicellular and autotrophic. They reproduce by spore formation. The structure of the plant body of bryophytes is flat, ribbon-like long, without true roots, stem and leaves. Instead, they have stem-like or leaf-like parts and root-like rhizoids. They do not have specific tissues for conduction of food and water. Examples are Moss (Funaria), Marchantia, Anthoceros, Riccia, etc.

Question 3.
Plants from Pteridophyta group have well developed roots, stem and leaves and separate …………….. for conduction of food and water. But,
they do not bear …………….. and ……………… They reproduce with the help of …………….. formed along the back or posterior surface of their leaves. Examples are ferns like Nephrolepis, Marsilea, Pteris, Adiantum, Equisetum, Selaginella, Lycopodium, etc. These plants reproduce …………….. by spore-formation and sexually by …………….. formation. They have a well-developed conducting system.
Answer:
Plants from Pteridophyta group have well developed roots, stem and leaves and separate tissues for conduction of food and water. But, they do not bear flowers and fruits. They reproduce with the help of spores formed along the back or posterior surface of their leaves. Examples are ferns like Nephrolepis, Marsilea, Pteris, Adiantum, Equisetum, Selaginella, Lycopodium, etc. These plants reproduce asexually by spore-formation and sexually by zygote formation. They have a well-developed conducting system.

Question 4.
Phanerogams plants which have special structures for …………….. and produce …………….. In these plants, after the process of reproduction, seeds are formed which contain the …………….. and stored food. During germination of the seed, the stored food is used for the initial growth of the embryo. Depending upon whether seeds are enclosed in …………….. a or not, phanerogams are classified into …………….. and ……………. .
Answer:
Phanerogams plants which have special structures for reproduction and produce seeds. In these plants, after the process of reproduction, seeds are formed which contain the embryo and stored food. During germination of the seed, the stored food is used for the initial growth of the embryo. Depending upon whether seeds are enclosed in a fruit or not, phanerogams are classified into gymnosperms and angiosperms.

Question 5.
Gymnosperms are mostly …………….., perennial and woody. Their stems are without …………….. The leaves form a …………….. These plants bear male and female flowers on different …………….. of the same plant …………….. of these plants do not have natural coverings, i.e. these plants do not form …………….. and are therefore called gymnosperms. (gymnos: naked, sperms: seeds). Examples Cycas, Picea (Christmas tree), Thuja (Morpankhi), Pinus (Deodar), etc.
Answer:
Gymnosperms are mostly evergreen, perennial • and woody. Their stems are without branches. The leaves form a crown. These plants bear male and female flowers on different sporophylls of the same plant. Seeds of these plants do not have natural coverings, i.e. these plants do not form fruits and are therefore called gymnosperms. (gymnos: naked, sperms: seeds). Examples Cycas, Picea (Christmas tree), Thuja (Morpankhi), Pinus (Deodar), etc.

Question 6.
The flowers of Angiosperms plants bear are their …………….. organs Flowers develop into …………….. and seeds are formed within …………….. . Thus, these seeds are ……………..; hence, they are called angiosperms (angios: cover, sperms: seeds). The plants whose seeds can be divided into two equal halves or dicotyledons are called …………….. plants and those whose seeds cannot be divided into equal parts are called …………….. plants.
Answer:
The flowers of Angiosperms plants bear are their reproductive orgAnswer: Flowers develop into fruits and seeds are formed within fruits. Thus, these seeds are covered; hence, they are called angiosperms (angios: cover, sperms: seeds). The plants whose seeds can be divided into two equal halves or dicotyledons are called dicotyledonous plants and those whose seeds cannot be divided into equal parts are called monocotyledonous plants.

Answer the questions in detail:

Question 1.
Write the characteristics of Thallophyta.
Answer:

Thallophyta plants grow mainly in water.
The group of plants, which do not have specific parts like root-stem-leaves-flowers but are autotrophic due to the presence of chlorophyll are called algae.
Algae show great diversity They may be unicellular or multicellular and microscopic or large.
Some of these are found in freshwater while some are found in saline water.
Various types of fungi like yeasts and moulds which do not have chlorophyll are also included in this group.
Examples: Spirogyra, Ulothrix, Ulva, etc.

Question 2.
Write the characteristics of Gymnosperms.
Answer:

Gymnosperms are mostly evergreen, perennial and woody.
Their stems are without branches.
The leaves form a crown.
These plants bear male and female flowers on different sporophylls of the same plant.
Seeds of these plants do not have natural coverings, i.e. these plants do not form fruits and are therefore called gymnosperms (gmnos: naked, sperms: seeds)
Examples: Cycas, Picea (christmas tree), Thuja, Pinus (deodar), etc.

Make concept diagram

Question 1.
Plant classification
Answer:

Question 2.
Taxonomy of carnivorous 1ant
Answer:

Question 3.
Taxonomy of mango plant
Answer:

9th Std Science Questions And Answers:

Useful and Harmful Microbes Class 9 Science Chapter 8 Questions And Answers Maharashtra Board

January 6, 2025January 5, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Science Solutions Chapter 8 Useful and Harmful Microbes Notes, Textbook Exercise Important Questions and Answers.

Std 9 Science Chapter 8 Useful and Harmful Microbes Question Answer Maharashtra Board

Class 9 Science Chapter 8 Useful and Harmful Microbes Question Answer Maharashtra Board

1. Complete the statements using the proper option from those given below. Explain the statements. (mycotoxins, budding, rhizobium)

a. Yeast reproduces asexually by the …………………….. method.
Answer:
The yeast cells develop small round bodies on the parent cell. These are called buds. New daughter cells develop from these buds.

b. Toxins of fungal origin are called …………………….. .
Answer:
Mycotoxins are poisonous chemicals released into the food by fungi. This makes the food poisonous.

c. Leguminous plants can produce more proteins due to …………………….. .
Answer:

(i) Nitrogenous compounds are required to produce proteins.
(ii) Rhizobia produce nitrogenous compounds by fixing atmospheric nitrogen and make it available for their host plants like leguminous plants.

2. Write the names of microbes found in the following food materials.
yogurt, bread, root nodules of leguminous plants, idli, dosa, spoiled potato curry.
Answer:

Food materials	Microbes
Yogurt	Lactobacilli
Bread	Yeast
Root nodules of leguminous plants	Rhizobium
Idli	Yeast, bacteria
Dosa	Yeast, bacteria
Spoiled potato curry	Clostridium

3. Identify the odd word out and say why it is the odd one?

a. Pneumonia, diphtheria, chicken pox, cholera.
Answer:
Chickenpox. It is caused by a virus, whereas others are caused by bacteria.

b. Lactobacilli, rhizobia, yeast, clostridia.
Answer:
Yeast. It is a fungus, whereas the rest are bacteria.

c. Root rot, rust (tambura), rubella, mozaic.
Answer:
Rubella. It is a disease of humans, whereas the rest are diseases of plants.

4. Give scientific reasons.

a. Foam accumulates on a the surface of ‘dal’ kept for a long time in summer.
Answer:

Dal is rich in proteins.
During summer, bacteria attack the dal and cause fermentation resulting in the production of carbon dioxide gas.
Therefore, foam accumulates on the surface of the ‘dal’ kept for long time in summer.

b. Why are naphthalene balls kept with clothes to be put away.
Answer:

Naphthalene balls are balls of chemical pesticide and deodorant.
They help to kill or repel insects such as moths, cockroaches, mice etc.
Therefore, naphthalene balls are kept with clothes to be put away to prevent clothes from getting damaged.

5. Write down the modes of infection and the preventive measures against fungal diseases.
Answer:

Mode of infection: Contact with infected person or his/her belongings like clothes.
Preventive measure: Personal hygiene and avoid contact with infected person.

6. Match the pairs.

‘A’ group ‘B’ group
1. Rhizobium a. Food poisoning
2. Clostridium b. Nitrogen fixation
3. Penicillium c. Bakery products
4. Yeast d. Production of antibiotics
Answer:
(1 – b),
(2 – a),
(3 – d),
(4 – c)

7. Answer the following questions.

a. Which vaccines are given to infants? Why?
Answer:

Hepatitis A and B, DTP (Diphtheria, Tetanus, Pertussis.) Polio, MMR (Measles, Mumps, Rubella), Chicken pox, Influenza, Tetanus, BCG, Rotavirus, etc.
Vaccines consist of dead or weakend microbes. When these are swallowed or injected, the body produces antibodies to fight them.
These antibodies remain in the body and protect it from any future attack of the disease causing microbes.
Therefore, vaccines are given to infants for preventing diseases.

b. How is a vaccine produced?
Answer:

Vaccines are made using the disease causing bacteria or virus but in a form that will not harm the human beings.
Vaccine is made from dead or weakened microbes or their toxins.
Vaccine stimulates the immune system to produce antibodies which give life-long protection against the disease.
There are specific vaccines for specific diseases.

c. How do antibiotics cure disease?
Answer:
Antibiotics cure diseases by destroying or preventing the growth of harmful micro-organisms.

d. Are the antibiotics given to humans and animals the same? Why?
Answer:

Generally, antibiotics work against any harmful bacteria, whether it is attacking humans or animals.
But some of them are better suited to humans while some are better for animals. This is due to the adverse effects they show in different species.
Also, the dosages of antibiotics for humans and animals differ.

e. Why is it necessary to safely store the pathogens of a disease against which vaccines are to be produced?
Answer:

Pathogens are microbes which can cause diseases in us.
For the preparation of a vaccine, a particular pathogen is cultured and grown in a laboratory.
If these pathogens are not safely stored, they many get modified due to environmental factors, resulting in decrease in the efficiency of the vaccine.
Also, the live pathogens may escape and cause diseases in us.

8. Answer the following questions in brief.

a. What are ‘broad-spectrum antibiotics’?
b. What is fermentation?
Answer:

Yeast uses sugar for food.
Yeast grows and multiplies rapidly due to the carbon compounds in the sugar solution.
In the process of obtaining nutrition, yeast cells convert the carbohydrates in the food into alcohol and carbon dioxide.
Also, the bacteria Lactobacilli convert lactose, the sugar in milk into lactic acid.
This process is called fermentation.

c. Define ‘Antibiotic’.
Answer:

Carbon compounds obtained from some bacteria and fungi for destroying or preventing the growth of harmful micro -organisms are called antibiotics.
Antibiotics, a discovery of the 20th century, have brought a revolution in the field of medicine.
Antibiotics mainly act against bacteria. Some antibiotics can destroy protozoa.
Some antibiotics are useful against a wide variety of bacteria they are called broad-spectrum antibiotics. Examples – Ampicillin, amoxicillin, tetracycline, etc.
When the pathogen cannot be identified even though the symptoms of the disease are visible, broad-spectrum antibiotics are used.
Whenever a pathogenic micro-organism is definitely known, then narrow-spectrum antibiotics are used. Examples: Penicillin, gentamycin, erythromycin, etc.

Class 9 Science Chapter 8 Useful and Harmful Microbes Intext Questions and Answers

Can you recall?

Question 1.
What is meant by microbes? What are their characteristics?
Answer:
Microbes are tiny microscopic organisms which cannot be seen with the unaided eye.

Characteristics of Microbes.

They are the smallest organisms on earth.
They are composed of prokaryotic or eukaryotic cells.
They can be seen only with the help of a microscope.
They are found in any kind of environment ranging from coolest polar regions to hottest of deserts. Also found in soil, water and air.
Some of them are useful, whereas some of them are harmful micro-organisms.

Question 2.
How do you observe microbes?
Answer:
Microbes are observed using a microscope.

Answer the following.

Question 1.
Why are wineries located near Nashik in Maharashtra?
Answer:

Nashik in Maharashtra is the leading grape producer in the country as it has the soil suitable for the production of grapes.
Glucose and fructose, the sugars present in grape juice are fermented with the help of yeast to produce wines. Therefore, wineries are located near Nashik in Maharashtra.

Question 2.
Find out the uses of fungi to plants and animals?
Answer:

Fungi decompose the bodies of dead animals and convert them into simple carbon compounds. These substances easily mix with air, water and soil from where they are again absorbed by plants and enter the food chain.
Some fungi living in symbiotic association with plants help to absorb water and inorganic compounds like nitrate and phosphate.
Fungi are also used to derive antibiotics like penicillin which are useful to animals.
Ants grow fungi in their anthill and obtain food from it.
Some species of wasps and insects lay their eggs in the fungal bodies growing on trees, thus ensuring a food supply for their larvae.

Question 3.
What is the structure of lichen, a condiment? Where else is it used?
Answer:

Lichen is a symbiotic association between a fungus and an algae (Cyanobacterium).
Lichens are sensitive to environmental disturbances and are used in assessing air pollution in an area.
Lichens are also used in making dyes, perfumes and in traditional medicines.
A few lichen species are eaten by insects or animals such as reindeer.

Open-ended questions

Answer the following questions:

Class 9 Science Chapter 8 Useful And Harmful Microbes Exercise Question 1.
How is yoghurt made from milk? What exactly happens in this process?
Answer:

Milk contains sugar called lactose which is broken down with help of Lactobacilli.
Lactobacilli converts lactose into Lactic Acid. This process is called fermentation. As a result, the pH of milk decreases causing coagulation of milk proteins.
Thus, milk proteins are separated from other constituents of milk and milk changes to yoghurt.

Useful And Harmful Microbes Class 9 Exercise Question 2.
Sometimes, you may notice a black powder or white discs floating on the pickle or murabba, when a jar is opened after a long time. What exactly is this? Why are such food items not good to eat?
Answer:

A black powder or white disc floating on the pickle or murabba are fungi.
Different fungal species depend on host (pickle and murabba) for their growth and reproduction.
During this process, fungi secretes mycotoxins which are poisonous chemicals; which ultimately spoil the food. Consuming such food can cause food poisoning.
Therefore, such food items are not good to eat.

8 Useful And Harmful Microbes Class 9 Question 3.
How many different industries depend upon the Lactobacilli bacteria?
Answer:
Industries like milk products, cider, cocoa, pickles, pharmaceuticals depend on Lactobacilli bacteria.

Useful And Harmful Microbes Class 9 Question 4.
Which types of cottage industries and factories can be started in areas with abundant milk production?
Answer:
Cottage industries like the manufacture of milk products like ghee, cheese, paneer, curd, shrikhand, etc. and chocolate making can be started in areas with abundant milk production.

9th Class Science Chapter 8 Useful And Harmful Microbes Exercise Question 5.
Which changes do you notice in leather articles and gunny (jute) bags during the rainy season?
Answer:
In rainy season we can notice whitish-green cotton-like growth or black powder or white discs on leather articles and gunny (jute) bags during the rainy season as these articles are infected by fungus.

Class 9th Science Chapter 8 Useful And Harmful Microbes Exercise Question 6.
For how long afterwards can you use those articles?
Answer:
Those articles cannot be used for long as they wear out and do not last long.

Question 7.
Why do these articles not get spoilt during the summer or winter?
Answer:

Spores of fungi can germinate when there is sufficient moisture.
During summer or winter the weather is hot and dry and so fungus cannot grow in such weather.
Also microbes cannot survive extreme hot or cold temperatures of summer or winter. Therefore, these articles do not get spoilt during summer or winter.

Question 8.
Why do doctors advise you to take yoghurt or buttermilk if you have indigestion or abdominal discomfort?
Answer:

The Lactobacilli present in yoghurt or buttermilk help to restore the natural microbial flora in the intestine, thus helping in digestion and absorption of nutrients.
Also buttermilk helps to cool down the stomach and works as a laxative to ease the congestion during abdominal discomfort.

Question 9.
Sometimes, yoghurt becomes bitter and froths up. Why does this happen?
Answer:

Sometimes yoghurt becomes bitter due to excess fermentation by bacteria.
Excess amount of lactic acid is produced making the curd bitter.

Question 10.
Which different milk products are obtained at home by fermentation of the cream from the milk?
Answer:
Yoghurt, buttermilk, ghee, cheese, shrikhand, sour cream, etc.

Question 11.
Recently, it has been made compulsory in India and some other countries to mix 10% ethanol with fuels like petrol and diesel. What is the reason for this?
Answer:

Ethanol is a smokeless and high quality fuel. So it helps to reduce pollution when mixed with petrol or diesel.
As petrol or diesel is a fossil fuel less consumption of it will lead to resourceful use of it and making the country self-efficient by moving towards sustainable fuel like ethanol.

Question 12.
Chapattis made from wheat only swell up but bread becomes spongy, soft and easy to digest. Why is it so?
Answer:

The chapatti dough has water, which on heating converts into steam and tries to escape.
While doing so, it lifts up the upper layer of the chapatti. Therefore, the chapatti swells up.
Bread is made by adding yeast to the flour.
In the process of obtaining nutrition, the yeast cells convert the carbohydrates into alcohol and carbon dioxide.
When this dough is baked, the carbon dioxide escapes out making the bread spongy, soft and easy to digest.

Question 13.
Salt is applied on the inner surface of pickle jars and the pickle is covered with oil. Why is this done?
Answer:

Salt acts as a preservative. It prevents the growth of bacteria by forcing the microbes to lose water by osmosis. Hence, salt is applied on the inner surface of pickle jars.
Pickle is covered with oil as oil acts as preservative. It seals off the air from the item that is being pickled and provides an environment in which microbes cannot grow.

Question 14.
Which preservatives are mixed with ready to eat foods to prevent them from spoiling?
Answer:
Common salt, sugar, sodium benzoate, citric acid, sodium meta-bi-sulfite etc. are some 1 of the preservatives mixed with ready-to-eat foods to prevent them from spoiling.

Question 15.
Which plant and animal diseases are caused by micro-organisms and what are the 1 measures to be taken against them? Answer:
Plant diseases:

Citrus canker is a bacterial disease that affects 1 trees of citrus fruits.
Rust of wheat is a fungal disease that affects wheat crops.
Yellow vein mosaic is a viral disease which affects vegetables like bhindi (okra).

Preventive Measures:

Seeds which are healthy and disease-free should be selected for sowing.
Infected plants should be removed.
Plants should be sprayed with fungicides and germicides to prevent diseases.

Animal diseases:

Anthrax is a disease that affects cattle. It is caused by a bacterium.
Foot and mouth is a dangerous disease in cattle caused by a virus.
Rabies is a viral disease that affects animals.

Preventive Measures:

The place where animals are kept should be washed with germicides.
Animals should be dewormed regularly.
The animals should be treated with necessary antibiotics for infectious diseases.
They should be regularly vaccinated.
Take the animals to a veterinary hospital for proper treatment and vaccination.

Answer the following questions:

Question 1.
Bring ‘active dry yeast’ from the market. Mix a spoonful of yeast, two spoonfuls sugar with a sufficient quantity of lukewarm water in a bottle. Fix a colourless, transparent balloon on the mouth of that bottle.

What changes do you observe after 10 minutes? Mix limewater with the gas accumulated in the balloon. Collect that limewater in a beaker and observe it. What do you notice?

Answer:

After 10 minutes, the balloon is filled with a gas and gets inflated.
Lime water turns milky thus proving that the gas accumulated is carbon dioxide.

Class 9 Science Chapter 8 Useful and Harmful Microbes Additional Important Questions and Answers

Select the correct option:

Question 1.
The rod-shaped bacteria found in milk or buttermilk are called ……………………. .
(a) Rhizobium
(b) Clostridium
(c) Lactobacilli
(d) Saccharomyces
Answer:
(c) Lactobacilli

Question 2.
Yoghurt has a specific sour taste due to ……………………. .
(a) lactic acid
(b) citric acid
(c) acetic acid
(d) alcohol
Answer:
(a) lactic acid

Question 3.
Bacteria found in the root nodules of leguminous plants are ……………………. .
(a) clostridium
(b) streptococcus
(c) Lactobacilli
(d) Rhizobium
Answer:
(d) Rhizobium

Question 4.
A mutually beneficial relationship is called ……………………. .
(a) symbiosis
(b) parasitism
(c) autotropism
(d) none of these
Answer:
(a) symbiosis

Question 5.
Carbon compounds obtained from bacteria and fungi for destroying or preventing the growth of harmful micro-organisms are called ……………………. .
(a) probiotics
(b) antibiotics
(c) antibodies
(d) antigens
Answer:
(b) antibiotics

Question 6.
Fungi release ……………………. into the food, making the food poisonous.
(a) cyanotoxins
(b) dinotoxins
(c) mycotoxins
(d) cytotoxins
Answer:
(c) mycotoxins

Question 7.
……………………. produce bottle-shaped endospores in adverse conditions.
(a) Lactobacilli
(b) Clostridium
(c) Yeast
(d) Rhizobium
Answer:
(b) Clostridium

Question 8.
……………………. conducted important research on the toxin responsible for gas gangrene and the antitoxin responsible for treating it.
(a) Ida Bengston
(b) Van Ermengem
(c) Louis Pasteur
(d) Alexander Fleming
Answer:
(a) Ida Bengston

Question 9.
……………………. is a smokeless and high quality fuel.
(a) Methanol
(b) Ethanol
(c) Petrol
(d) Diesel
Answer:
(b) Ethanol

Question 10.
Antibiotics mainly act against ……………………. .
(a) bacteria
(b) viruses
(c) algae
(d) fungi
Answer:
(a) Bacteria

Question 11.
……………………. is a broad-spectrum antibiotic.
(a) Gentamycin
(b) Penicillin
(c) Amoxicillin
(d) Erythromycin
Answer:
(c) Amoxicillin

Question 12.
……………………. is a narrow-spectrum antibiotic.
(a) Ampicillin
(b) Amoxicillin
(c) Tetracyclin
(d) Penicillin
Answer:
(d) Penicillin

Question 13.
Antibiotic penicillin was discovered by ……………………. .
(a) Louis Pasteur
(b) Alexander Fleming
(c) Ida Bengston
(d) Van Ermengem
Answer:
(b) Alexander Fleming

Question 14.
……………………. proved that the anaerobic bacterium Clostridium botulinum is responsible for food poisoning.
(a) Louis Pasteur
(b) Ida Bengston
(c) Alexander Fleming
(d) Van Ermengem
Answer:
(d) Van Ermengem

Question 15.
AIDS is caused by ……………………. .
(a) virus
(b) bacteria
(c) protozoa
(d) fungi
Answer:
(a) Virus

Question 16.
Dengue is caused by ……………………. .
(a) droplets spread in air
(b) contact with infected person
(c) mosquito bite
(d) contaminated water and food
Answer:
(c)mosquitobite

Question 17.
Pneumonia is caused by ……………………. .
(a) virus
(b) bacteria
(c) fungi
(d) protozoa
Answer:
(b) bacteria

Question 18.
……………………. can be prevented by vaccination.
(a) Malaria
(b) AIDS
(c) Leprosy
(d) Chicken pox
Answer:
(d) Chicken pox

Question 19.
Malaria is caused by ……………………. .
(a) protozoa
(b) bacteria
(c) fungi
(d) virus
Answer:
(a) protozoa

Question 20.
Bird flu (H₇N₉) and swine flu (H₁N₁) are caused by ……………………. .
(a) bacteria
(b) protozoa
(c) fungi
(d) virus
Answer:
(d) virus

Question 21.
The Lactobacilli convert lactose, the sugar in the milk, into ……………………. .
(a) lactic acid
(b) acetic acid
(c) alcohol
(d) citric acid
Answer:
(a) lactic acid

Question 22.
The ……………………. destroys harmful microbes present in the milk.
(a) high pH
(b) neutral pH
(c) low pH
(d) none of these
Answer:
(c) low pH

Question 23.
Lactobacilli kill the harmful bacteria like ……………………. present in the alimentary canal.
(a) Rhizobium
(b) Saccharomyces
(c) Clostridium
(d) Alcanivorax
Answer:
(c) Clostridium

Question 24.
During fermentation, yeast cells convert carbohydrates into ……………………. .
(a) glucose and fructose
(b) alcohol and carbon dioxide
(c) proteins and fats
(d) fatty acids and amino acids
Answer:
(b) alcohol and carbon dioxide

Question 25.
Molasses is fermented with the help of yeast called ……………………. .
(a) Yarrowia lipolytica
(b) Alcanivorax
(c) Rhizobia
(d) Saccharomyces
Answer:
(d) Saccharomyces

Question 26.
A yeast ……………………. is used to absorb the toxins released during the production of palm oil.
(a) Yarrowia lipolytica
(b) Alcanivorax
(c) Saccharomyces cerevisiae
(d) Penicillium
Answer:
(a) Yarrowia lipolytica

Question 27.
The bacteria which spoil cooked food are ……………………. .
(a) Saccharomyces
(b) Lactobacilli
(c) Clostridium
(d) Rhizobium
Answer:
(c) Clostridium

Question 28.
……………………. can grow and reproduce only in living cells.
(a) Bacteria
(b) Viruses
(c) Fungi
(d) Protozoa
Answer:
(b) Viruses

Find the odd man out:

Question 1.
AIDS, Hepatitis, Leprosy, Dengue.
Answer:
Leprosy. It is caused by bacteria, whereas the rest are caused by viruses.

Question 2.
Cholera, Leprosy, Pneumonia, Influenza.
Answer:
Influenza. It is caused by a virus, whereas the rest are caused by bacteria.

Question 3.
Ampicillin, Amoxycillin, Penicillin, Tetracycline.
Answer:
Penicillin. It is a narrow-spectrum antibiotic, whereas others are broad-spectrum antibiotics.

Question 4.
Tetracycline, Penicillin, Gentamycin, Erythromycin.
Answer:
Tetracycline. It is a broad-spectrum antibiotic, whereas others are narrow-spectrum antibiotics.

Complete the analogy:

Question 1.
(1) Dengue : Virus :: Malaria : …………………………. .
(2) Hepatitis : Virus :: Pneumonia : …………………………. .
(3) Cholera : Bacteria :: Swine flu : …………………………. .
(4) Swine flu : HJNJ : : Bird Flu : …………………………. .
(5) Measles : Virus :: Ringworm : …………………………. .
(6) Yoghurt: Lactobacilli : : Bread : …………………………. .
(7) Oil spills: Alcanivorax :: Absorption of arsenic : …………………………. .
(8) Rhizobium : Nitrogen fixation : : Clostridium : …………………………. .
Answer:
(1) Protozoa
(2) Bacteria
(3) Virus
(4) HyN9
(5) Fungi
(6) Yeast
(7) Saccharomyces cerevisiae
(8) Food poisoning.

Match the columns:

Question 1.

Column ‘A’	Column ‘B’
(1) Leprosy	(a) Virus
(2) Ringworm	(b) Fungi
(3) Influenza	(c) Protozoa
(4) Malaria	(d) Bacteria

Answer:
(1 – d),
(2 – b),
(3 – a),
(4 – c)

State whether the following statements are true or false. Correct the false statements:

(1) Lactobacilli are aerobic bacteria.
(2) Lactobacilli converts lactose sugar into alcohol.
(3) Yoghurt has a specific sour taste due to acetic acid.
(4) The bacteria Clostridium are present in the root . nodules of leguminous plants.
(5) Yeast cell is a prokaryotic cell.
(6) The use of Rhizobium has helped to reduce the use of chemical fertilizers.
(7) Ethanol is a smokeless and high quality fuel.
(8) A yeast, Saccharomyces cerevisiae is used for absorbing toxins released during palm oil production.
(9) Gentamycin is a narrow-spectrum antibiotic.
(10) Antibiotics mainly act against bacteria.
(11) Oil spills in oceans are cleared with the help of Clostridium bacteria.
(12) Tetracycline is a narrow-spectrum antibiotic.
(13) Amoxicillin is a broad-spectrum antibiotic.
(14) Penicillin is a group of antibiotics obtained from a fungus Saccharomyces.
(15) Antibiotic Penicillin was discovered by Alexander Fleming.
(16) The bacteria Lactobacilli cause food-poisoning.
(17) Clostridium bacteria grow in aerobic conditions.
(18) AIDS is caused by a virus.
(19) Influenza is caused by a bacteria.
(20) Antibiotics useful to one person can be suggested to others also.
(21) Dengue is caused by a bacteria.
(22) Dandruff and ringworm are caused by fungi.
(23) Pneumonia is spread through droplets spread in air by infected person.
(24) Chicken pox spread due to contaminated food and water.
(25) Ida Bengston was honoured with the Typhoid Medal’ in 1947.
Answer:
(1) False. Lactobacilli are anaerobic bacteria.
(2) False. The Lactobacilli converts lactose sugar into lactic acid.
(3) False. Yogurt has a specific sour taste due to lactic acid.
(4) False. The bacteria Rhizobium are present in the root nodules of leguminous plants.
(5) False. Yeast cell is a eukaryotic cell.
(6) True.
(7) True.
(8) False. A yeast, Yarrowia lipolytic is used to absorb the toxins released during the production of palm oil.
(9) True.
(10) True.
(11) False. Oil spills in oceans are cleared with the help of Alcanivorax bacteria.
(12) False. Tetracycline is a broad-spectrum antibiotic.
(13) True.
(14) False. Penicillin is a group of antibiotics obtained from a fungus Penicillium.
(15) True.
(16) False. The bacteria Clostridium cause food? poisoning.
(17) False. Clostridium bacteria grow in anaerobic conditions.
(18) True.
(19) False. Influenza is caused by a virus.
(20) False. Antibiotics useful to one person cannot be suggested to others as different diseases require different antibiotics.
(21) False. Dengue is caused by a virus.
(22) True.
(23) True.
(24) False. Chicken pox spread due to contact with infected person.
(25) False. Ida Bengston was honoured with the ‘Typhus Medal’ in 1947.

Complete the statements using the proper option from those given below. Explain the statements: (mycotoxins, budding, Rhizobium, molasses, endospores, broad-spectrum, Lactobacilli)

Question 1.
Lactobacilli bacteria are used for making yoghurt.
Answer:
The lactobacilli convert lactose, the sugar in the milk, into lactic acid. As a result, the pH of milk decreases causing a coagulation of milk proteins. Milk changes into yogurt.

Question 2.
The use of Rhizobium has helped to reduce the use of chemical fertilizers.
Answer:
Rhizobium bacteria are found in the root nodules of leguminous plants. They help to convert atmospheric nitrogen into nitrogen compounds and provide it to the plants. This helps to reduce the use of chemical fertilizers and their adverse effects.

Question 3.
Amoxicillin is a broad-spectrum antibiotic.
Answer:
This antibiotic is useful against a wide variety of bacteria. It is used against pathogens which cannot be identified during symptoms of a disease.

Question 4.
Ethanol is produced by the fermentation of molasses.
Answer:
Molasses is produced from sugarcane juice. It is rich in carbohydrates. When it is fermented with the help of the yeast called Saccharomyces, ethanol (C2H5OH) is produced.

Question 5.
Clostridium bacteria produce bottle-shaped endospores.
Answer:
These endospores help them to survive in adverse conditions.

Give scientific reasons:

Question 1.
Lactobacilli are used for making yoghurt from milk.
Answer:

Lactobacilli convert lactose, the sugar in the milk, into lactic acid. This process is called fermentation.
As a result, the pH of milk decreases causing coagulation of milk proteins.
Thus, milk proteins are separated from other constituents of milk and milk changes into yoghurt.
Yoghurt has a specific sour taste due to lactic acid. The low pH destroys harmful microbes present in the milk. Therefore, Lactobacilli are used for making yoghurt from milk.

Question 2.
Antibiotics should be taken only when prescribed by a doctor.
Answer:

Antibiotics are a group of medicines used to kill disease-causing bacteria and certain protozoa.
The doctor selects and prescribes the antibiotic best suited for our disease.
If taken in extra dose, they can kill the useful bacteria present in our body.
If the course of antibiotics is not completed, the bacteria develop resistance to that antibiotic making it ineffective.
Therefore, antibiotics should be taken only when prescribed by a doctor.

Question 3.
Nowadays, seeds are coated with Rhizobial solution or powder before sowing.
Answer:

When seeds coated with Rhizobial solution or powder are sown, Rhizobia enter the plantlets.
This is called Rhizobial inoculation.
Rhizobia can produce nitrogenous compounds from atmospheric nitrogen.
This experiment has helped in the supply of nitrogen to cereal and other crops, besides leguminous crops.
Therefore, nowadays seeds are coated with Rhizobial solution or powder before sowing.

Question 4.
Antibiotics are not effective against common cold or influenza.
Answer:

Antibiotics are a group of medicines used to control inflections caused by bacteria.
Common cold or influenza is caused by a virus.
Antibiotics are not effective against viruses.
Therefore, antibiotics are not effective against common cold or influenza.

Question 5.
Cotton fabrics, gunny bags, leather items and wooden items do not last long.
Answer:

Microscopic spores of fungi are present in the air.
If there is sufficient moisture, spores germinate on cotton fabric, gunny bags, leather, wooden items etc.
The fungal hyphae (fibres of the fungus) penetrate deep into the material to obtain nutrition and to reproduce.
This causes the materials to wear and become weak.
As a result, cotton fabric, gunny bags, leather and wooden items do not last long.

Question 6.
Food on which fungi has grown cannot be eaten.
Answer:

Various species of fungi grow on food items like pickles, murabba, jam, sauce, chutney etc.
They use the nutrients in these food items for growth and reproduction.
During this activity, fungi release mycotoxins, certain poisonous chemicals, into the food and thus food becomes poisonous.
Hence, the food on which fungi have grown cannot be eaten.

Write short notes:

Question 1.
Rhizobial inoculation.
Answer:

Nowadays, seeds are coated with rhizobial solution or powder before sowing.
After sowing, Rhizobia enter the plantlets.
This is called Rhizobial inoculation.
This experiment has helped in the supply of nitrogen to cereal and other crops, besides leguminous crops.

Question 2.
Bio-remediation.
Answer:

Bio-remediation is a technique that involves the use of organisms to break down environmental pollutants.
Generally, fungi like yeast and bacteria are used for bio-remediation.
A yeast, Yarrowia lipolytica is used to absorb the toxins released during the production of palm oil and the heavy metals and minerals released in some other industrial processes.
Saccharomyces cerevisiae is used for absorption of a pollutant, arsenic.
Oil spills in oceans are cleaned with the help of Alcanivorax bacteria.

Question 4.
Clostridium.
Answer:

Clostridium are the bacteria that spoil food.
Out of about 100 different species of this bacterium, some are free living in the soil whereas some live in the alimentary canals of humans and other animals.
These bacteria are rod-shaped and produce bottle-shaped endospores in adverse conditions.
One special characteristic of these bacteria is that they cannot withstand the normal oxygen level of the air because they grow in anaerobic conditions.

Write down the mode of infection and preventive measures for the following:

Question 1.
Write down the causative pathogen, mode of infection and preventive measures of AIDS.
Answer:

Causative Pathogen: Virus.
Mode of infection: Through blood and semen of infected person and milk of mother suffering from AIDS.
Preventive measure: Safe sexual contact, avoid resuse of needles and injections.

Question 2.
Write down the modes of infection and preventive measures against Bird Flu (H7N9) and Swine Flu (HjN.,).
Answer:

Mode of infection: Contact with infected birds and animals.
Preventive measure: Personal hygiene, properly cooked meat.

Question 3.
Write down the modes of infection and preventive measures against Malaria and dengue.
Answer:

Mode of infection: Mosquito bite, unclean surroundings.
Preventive measure: Cleanliness of surroundings, preventing stagnation of water, controlling mosquitoes.

Question 4.
Write down the modes of infection and preventive measures against Pneumonia.
Answer:

Mode of infection: Droplets spread in air by infected person.
Preventive measure: Vaccination, avoiding contact with infected person.

Question 5.
Write down the modes of infection and preventive measures for leprosy.
Answer:

Mode of infection: Long term contact with infected person.
Preventive measure: Avoiding contact with infected persons and their belongings.

Question 5.
What are the modes of infection and preventive measures for Hepatitis?
Answer:

Mode of infection: Contaminated water and food.
Preventive measure: Use clean and filtered water, proper storage of food.

Question 6.
What are the modes of infection and preventive measures for Influenza.
Answer:

Mode of infection: Contact with infected person.
Preventive measure: Personal hygiene and avoiding contact with infected person.

Answer the following questions:

Question 1.
How is bread made?
Answer:

Bread is made using flour, yeast, salt and water. The yeast uses sugar as food.
In the process of obtaining nutrition, yeast cells convert the carbohydrates into alcohol and carbon dioxide. This process is called fermentation.
The bubbles of carbon dioxide given off cause the dough to rise.
This dough can be used to make bread.
When this dough is baked, more bubbles of carbon dioxide reformed due to heat. As the gas escapes, the bread rises and becomes soft and fluffy.

Question 2.
What is the advantage of Rhizobium to farmers?
Answer:

The use of Rhizobium has helped to reduce the use of chemical fertilizers and thereby their adverse effects.
It has also helped to reduce expenses on fertilizers and thus benefited the farmers.

Question 3.
How can we observe Lactobacilli in buttermilk?
Answer:

Smear a drop of fresh buttermilk on a glass slide.
Stain it with methylene blue and put a coverslip over it.
Observe the smear under the 10X objective of a compound microscope and then with the more powerful 60X objective.
The blue rod-shaped organisms moving about are Lactobacilli.

Question 4.
What is symbiosis? Give example.
Answer:

Symbiosis is a mutually beneficial relationship.
Example: Rhizobium living in root nodules of leguminous plants supply nitrates, nitrites and amino acids to that plant and in exchange get energy in the form of carbohydrates.

Complete the following table:

Question 1.
The spread and prevention of disease
Answer:

Question 2.
Different species of Clostridium bacteria and the diseases caused by them.
Answer:

Species of Clostridium	Diseases
Clostridium tetani	Tetanus
Clostridium perfringens	Food poisoning
Clostridium botulinum	Botulism (Paralysis of muscles)
Clostridium difficile	Colitis (Infection of the intestine)

Answer in detail:

Question 1.
How is alcohol produced?
Answer:

Alcohol is often produced along with sugar in sugar factories.
Molasses is produced from sugarcane juice. It is rich in carbohydrates.
Molasses is fermented with the help of the yeast Saccharomyces.
In this process, ethanol (C₂H₅OH) alcohol is produced as a primary product and ester and other alcohols are produced as secondary products.
Besides molasses, maize, barley and other grains are also used for industrial production of alcohol.
Glucose and fructose, the sugars present in grape juice are also fermented with the help of yeast to produce alcohol which is used to make wines.

Question 2.
Give the uses of Lactobacilli.
Answer:
Uses of Lactobacilli:

Various milk products like yoghurt, buttermilk, ghee, cheese, shrikhand, etc. can be obtained by fermentation of milk.
Lactobacilli fermentation is useful for large scale production of cider, cocoa, pickles of vegetables etc.
Lactobacilli and some other useful microbes taken together are used to treat abdominal discomfort.
Leavened fodder offered to domestic cattle like cows and buffaloes is fodder fermented with the help of lactobacilli.
The Lactobacilli fermentation process is used to make wine and some types of bread.

Question 3.
What is Penicillin? What is it used for?
Answer:

Penicillin is a group of antibiotics obtained from a fungus, penicillium.
It is used for controlling the infections caused by bacteria like Staphylococci, Clostridia, Streptococci, etc.
Medicines containing Penicillin are useful to treat certain bacterial infections of the ear, nose, throat and skin as well as diseases like Pneumonia and scarlet fever.

Question 4.
How was the antibiotic penicillin discovered?
Answer:

Alexander Fleming, a professor of microbiology at St. Mary’s Hospital had cultured varieties of bacteria and fungi in petri dishes in his laboratory.
On 3rd September 1928, while observing Staphylococci cultures, he made an interesting observation in one petri dish.
In that petri dish, fungal colonies had grown but the area around those colonies was clean and clear, i.e. the bacteria had actually been destroyed.
After further studies, he confirmed that the fungus growing there was Penicillium and its secretion had destroyed the bacterial colonies.
Thus, the first antibiotic – penicillin had been discovered accidentlly and this formed the basis to find cures for incurable diseases.

Question 5.
What are the precautions to be followed while taking antibiotics?
Answer:

Antibiotics should be taken only when prescribed by a doctor.
Don’t purchase any antibiotic from medical stores without a prescription from a doctor.
Don’t consume antibiotics on your own to treat common diseases like a throat infection, common cold or influenza.
Even if you feel well before completing of the prescribed course of the antibiotics, you must continue and complete it.
Don’t suggest to others the antibiotics which were useful to you.

Question 6.
How can we observe Rhizobium bacteria in the roots of leguminous plant?
Answer:

Take a plantlet of fenugreek, groundnut or any other bean and sterilize it with a 3 to 5% solution of hydrogen peroxide.
Afterwards, keep it in a 70% solution of ethyl alcohol for 4 to 5 minutes.
Clean the roots with sterile water and take thin sections of the root nodules.
Select a good section and place it an a solution of saffranin for 2 to 3 minutes.
Place the stained section on a glass slide, cover it with a coverslip and observe it under the compound microscope. The pinkish rod-shaped organisms are the Rhizobium bacteria.

9th Std Science Questions And Answers:

Measurement of Matter Class 9 Science Chapter 4 Questions And Answers Maharashtra Board

January 6, 2025January 5, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Science Solutions Chapter 4 Measurement of Matter Notes, Textbook Exercise Important Questions and Answers.

Std 9 Science Chapter 4 Measurement of Matter Question Answer Maharashtra Board

Class 9 Science Chapter 4 Measurement of Matter Question Answer Maharashtra Board

1. Give examples.

a. Positive radicals
Answer:
Na⁺– Sodium ion, K⁺ – Potassium ion

b. Basic radicals
Answer:
Na⁺ – Sodium ion, K⁺ – Potassium ion, Ag⁺ – Silver ion

c. Composite radicals
Answer:
\(\mathrm{SO}_{4}^{2-}, \mathrm{NH}_{4}^{+}\)

d. Metals with variable valency
Answer:
(a) Iron (Ferrum)
(i) Fe²⁺ – Ferrous [Iron – II]
(ii) Fe³⁺ – Ferric [Iron – III]

(b) Copper (Cuprum)
(i) Cu⁺ – Cuprous [Copper -1]
(ii) Cu²⁺ – Cupric [Copper – II]

e. Bivalent acidic radicals
Answer:
O^2- – Oxide, S^2- – Sulphide, \(\mathrm{CO}_{3}^{2-}\) – Carbonate

f. Trivalent basic radicals
Answer:
Al³⁺ – Aluminium, Cr³⁺ – Chromium, Fe³⁺ – Ferric.

2. Write symbols of the following elements and the radicals obtained from them, and indicate the charge on the radicals.
Mercury, potassium, nitrogen, copper, sulphur, carbon, chlorine, oxygen
Answer:

3. Write the steps in deducing the chemical formulae of the following compounds.
Sodium sulphate, potassium nitrate, ferric phosphate, calcium oxide, aluminium hydroxide
Answer:
In order to write the chemical formulae of compounds, it is necessary to know the symbols and valency of various radicals.

1. Sodium Sulphate:
Step – 1 : To write the symbols of the radicals (Basic radicals on the left and acidic radicals on the right)
\(\mathrm{Na} \quad \mathrm{SO}_{4}\)
Step – 2 : To write the valency below the respective radical.

Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
Na₂ SO₄
(Sodium sulphate)

2. Potassium Nitrate:
Step -1 : To write the symbols of the radicals (Basic radicals on the left and acidic radicals on the right)
K NO₃
Step – 2 : To write the valency below the respective radical.
\(\begin{array}{cc}
\mathrm{K} & \mathrm{NO}_{3} \\
1 & 1
\end{array}\)
Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
KNO₃
(Potassium nitrate)

3. Ferric phosphate:
Step -1 : To write the symbols of the radicals (Basic radicals on the left and acidic radicals on the right)
Fe PO₄
Step – 2 : To write the valency below the respective radical.

Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
FePO₄
(Ferric phosphate)

4. Calcium oxide:
Step – 1 : To write the symbols of the radicals (Basic radical on the left and acidic radicals on the right)
Ca O
Step – 2 : To write the valency below the respective radical.

Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
CaO
(Calcium oxide)

5. Aluminium hydroxide:
Step – 1 : To write the symbols of the radical (Basic radical on the left and acidic radical on the right)
Al OH
Step – 2 : To write the valency below the respective radical.

Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
Al(OH)₃
(Aluminium hydroxide)

6. Calcium carbonate:
Step – 1 : To write the symbols of the radical (Basic radical on the left and acidic radicals on the right)
Ca CO₃
Step – 2 : To write the valency below the respective radical.

Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
CaCO₃
(Calcium Carbonate)

7. Sodium dichromate:
Step – 1 : To write the symbols of the radicals (Basic radical on the left and acidic radical on the right)
Na Cr₂O₇
Step – 2 : To write the valency below the respective radical.
\(\begin{array}{cc}
\mathrm{Na} & \mathrm{Cr}_{2} \mathrm{O}_{7} \\
1 & 2
\end{array}\)
Step – 3: To cross-multiply as shown by arrows the number of radicals.

Step – 4 : To write down the chemical formula of the compound.
Na2Cr₂O₇
(Sodium dichromate)

4. Write answers to the following questions and explain your answers.

a. Explain how the element sodium is monovalent.

Answer:

The number of protons or electrons (atomic number) in Sodium (Na) atom is 11. Therefore the electronic configuration of sodium atom is (2, 8,1).
In chemical reaction, sodium atom has the capacity to give away le_ from its outermost orbit to form Na+ ion with stable electronic configuration (2, 8).
As sodium atom gives away le- and a cation of sodium is formed, hence the valency of sodium is 1 and therefore, the element sodium is monovalent.

b. M is a bivalent metal. Write down the steps to find the chemical formulae of its compounds formed with the radicals, sulphate and phosphate.
Answer:
M is a bivalent metal. Following are the steps to find the chemical formulae of its compounds formed with the radicals, sulphate and phosphate:

(i) Compound of metal ‘M’ with radical sulphate
Step – 1: To write the symbols of the radicals (Basic radicals on the left and acidic radicals on the right)
M SO₄
Step – 2: To write the valency below the respective radical.

Step – 3: To cross multiply as shown by arrows the number of radicals.

Step – 4: To write down the chemical formula of the compound.
M SO₄

(ii) Compound of metal ‘M’ with radical phosphate.
Step – 1: To write the symbols of the radicals (Basic radicals on the left and acidic radicals on the right)
M PO₄
Step – 2: To write the valency below the respective radical.

Step – 3: To cross multiply as shown by arrows the number of radicals.

Step – 4: To write down the chemical formula of the compound.
M₃ (PO₄)₂

c. Explain the need for a reference atom for atomic mass. Give some information about two reference atoms.
Answer:

The mass of an atom is concentrated in its nucleus and it is due to the protons (p) and neutrons (n) in it.
Since an atom is very very tiny, it was not possible to measure atomic mass accurately. Therefore, the concept of relative mass of an atom was formed.
To express relative mass of an atom, reference of atom is considered. The two reference atoms were as follows:

(a) Hydrogen (H) atom: The hydrogen atom is the lightest. The relative mass of a hydrogen atom is 1 which has only 1 proton in its nucleus. On this scale, the relative atomic mass of many elements comes out to be fractional. Therefore, carbon was selected as a reference atom.

(b) Carbon (C) atom: The carbon atom is selected as reference atom. In this scale, the relative mass of a carbon atom is accepted as 12.

The relative atomic mass of 1 hydrogen (H) atom compared to the carbon (C) atom becomes

d. What is meant by Unified Atomic Mass.
Answer:

During earlier time, relative mass of an atom was considered for measuring the mass of an atom directly. But since the founding of unified mass, relative mass is not accepted henceforth.
Unified atomic mass is the unit of atomic mass called as Dalton.
Its symbol is ‘u’. lu = 1.66053904 x 10^-27 kg.

e. Explain with examples what is meant by a ‘mole’ of a substance.
Answer:

A mole is that quantity of a substance whose mass in grams is equal in magnitude to the molecular mass of that substance in Daltons.
For example: Atomic mass of oxygen atom (O) is 16u. Thus, the molecular mass of oxygen molecule (O₂) is 16 x 2 = 32u. Therefore, 32 g of oxygen is 1 mole of oxygen.

5. Write the names of the following compounds and deduce their molecular masses.
Na₂SO₄, K₂CO₃, CO₂, MgCl₂, NaOH, AlPO₄, NaHCO₃
Answer:

6. Two samples ‘m’ and ‘n’ of slaked lime were obtained from two different reactions. The details about their composition are as follows:
‘sample m’ mass : 7g
Mass of constituent oxygen : 2g
Mass of constituent calcium : 5g
‘sample n’ mass : 1.4g
Mass of constituent oxygen : 0.4g
Mass of constituent calcium : 1.0g

Which law of chemical combination does this prove? Explain.
Answer:
(i) The expected proportion by weight of the constituent elements of quick lime that is calcium oxide would be from its known molecular formula CaO. The atomic mass of Ca and O are 40 and 16 respectively. This means, the proportion by weight of the constituent elements Ca and O in the compound CaO is 40 :16 which is 5 : 2.

(ii) Now, for the given sample’m’ of CaO = 5 g
mass of given sample = 7 g
mass of constituent Ca in sample’m’ = 5 g
mass of constituent O in sample’m’ = 2 g

(iii) This means that 7 g of calcium oxide contairis 5 g of calcium (Ca) and 2 g of oxygen (O); apd the proportion by weight of calcium and oxygen in it is 5 : 2.

(iv) Now, for the given sample ‘n’ of CaO mass of given sample CaO = 1.4 g
Mass of constituent Ca in sample ‘n’ = 1.0 g
Mass of constituent O in sample ‘n’ = 0.4 g
This means that 1.4g of calcium oxide contains 1.0 g of calcium (Ca) and 0.4 g of oxygen (O); and the proportion by weight of calcium and oxygen in it is 5 : 2.

(v) Above samples’m’ and ‘n’ of calcium oxide (CaO) shows that the proportion by weight of the constituent elements in different samples of a compound is always constant that is the proportion by weight of calcium (Ca) and oxygen (O) in different samples of calcium oxide (CaO) is constant.

(vi) The experimental value of proportion by weight of the constituent elements matched with the expected proportion calculated by molecular mass. This proves and verifies the law of constant proportion.

The law states that ‘The proportion by weight of the constituent elements in the various samples of a compound is fixed’.

7. Deduce the number of molecules of the following compounds in the given quantities.
32g oxygen, 90g water, 8.8g carbon dioxide, 7.1g chlorine.

Class 9 Science Chapter 4 Measurement Of Matter Notes Question 1.
32g oxygen
Answer:
Given : Mass of oxygen (O₂) m = 32g
To find : Number of molecules in 32g of oxygen.
Solution : Atomic mass of oxygen (O) = 16
∴ Molecular mass of oxygen (O₂) M = 16 x 2 = 32
According to the formula, Number of moles in the given O₂ (n)

1 mol of O₂ contains 6.022 x 10²³ molecules that is 32 g of 02 contains 6.022 * 10²³ molecules of O₂.
32g of oxygen contains 6.022 x 10²³ molecules of oxygen.

Class 9 Science Chapter 4 Measurement Of Matter Answers Question 2.
90g water
Answer:
Given : Mass of water (H₂O) m = 90g.
To find : Number of molecules in 90g of water.
Solution : Molecular mass of (H₂O) M = (Atomic mass of H) x 2 + (Atomic mass of O) x 1
∴ Molecular mass of (H₂O) M = 1 x 2 +16
∴ Molecular mass of (H₂O) M = 18
According to the formula,
Number of moles in the given H₂O (n)

1 mol of H₂O contains 6.022 x 10²³ molecules.
5 mol of H₂O contains 5 x 6.022 x 10²³ molecules. = 30.11 x 10²³ molecules, that is 90g of H₂O contains 30.11 x 10²³ molecules of H20.
90g of water contains 30.11 x 10²³ molecules of water.

4 Measurement Of Matter Exercise Question 3.
8.8g carbon dioxide
Answer:
Given : Mass of Carbon dioxide (CO₂)m = 8.8g.
To find : Number of molecules in 8.8g of carbon dioxide.
Solution : Molecular mass of (CO₂)M = (Atomic mass of C) x 1 + (Atomic mass of O) x 2
∴ Molecular mass of (CO₂)M = 12 x 1 + 16 x 2 = 12 + 32
Molecular mass of (CO₂)M = 44
According to the formula, Number of moles in the given CO₂ (n)

∴ 1 mol of CO₂ contains 6.022 x 10²³ molecules.
∴ 0.2 mol of CO₂ contains 0.2 x 6.022 x 10²³ molecules.
= 1.2044 x 10²³ molecules,
that is 8.8g of CO₂ contains 1.2044 x 10²³ molecules of CO₂.
8.8g of CO₂ contains 1.2044 x 10²³ molecules of CO₂.

Class 9 Science Solutions Maharashtra Board Question 4.
7.1g chlorine
Answer:
Given : Mass of Chlorine (Cl₂)m = 7.1g.
To find : Number of molecules in 7.1g of chlorine.
Solution : Atomic mass of (Cl) = 35.5
∴ Molecular mass of chlorine (Cl₂)M = 35.5 x 2 = 71
According to the formula, Number of moles in the given Cl₂ (n)

∴ 1 mol of Cl₂ contains 6.022 x 10²³ molecules.
∴ 0.1 mol of Cl₂ contains 0.1 x 6.022 x 10²³ molecules.
= 0.6022 x 10²³ molecules,
that is 7.1g of Cl₂ contains 0.6022 x 10²³molecules of Cl_2.
7.1g of Cl₂ contains 0.6022 x 10²³ molecules of chlorine.

8. If 0.2 mol of the following substances are required how many grams of those substances should be taken? Sodium chloride, magnesium oxide, calcium carbonate
Answer:
Given : Number of moles of sodium chloride (NaCl) n = 0.2 mol
To find : Mass in grams of 0.2 mol of NaCl
Solution:
Molecular mass of (NaCl)M = (Atomic mass of Na) x 1 + (Atomic mass of Cl) x 1
= 23 x 1 + 35.5 x 1
= 23 + 35.5
Molecular mass of (NaCl)M = 58.5
According to the formula,
Number of moles in the given NaCl (n)

Mass of NaCl in grams (m) = 0.2 x 58.5
Mass of NaCl in grams (m) = 11.7 g
Mass of 0.2 mole of NaCl is 11.7g

Class 9 Science Chapter 3 Current Electricity Intext Questions and Answers

Maharashtra State Board Class 9 Science Solutions Question 1.
What is the type of chemical bond in NaCl and MgCl₂?
Answer:

The type of chemical bond in NaCl and MgCl₂ is ionic bond.

9th Class Science Chapter 4 Measurement Of Matter Question 2.
Determine the valencies of H, Cl, O and Na from the molecular formulae H₂, HC1, H₂O and NaCl.
Answer:
(i) In the molecular formula HCl

∴ The valency of H is 1 and Cl is 1.

(ii) In the molecular formula H₂O

∴ The valency of H is 1 and O is 2.

(iii) In the molecular formula NaCl

∴ The valency of Na is 1 and Cl is 1.
∴ From all the above, the valencies of the given elements are as follows : H = 1, Cl = 1, O = 2 and Na = l.

Measurement Of Matter Class 9 Exercise Answers Question 3.
How is an element indicated in Chemistry?
Answer:
In chemistry an element is indicated by its symbol.

Question 4.
Write down the symbols of the elements you know.
Answer:
Symbols of some elements are

Hydrogen – H
Helium – He
Boron – B
Carbon – C
Aluminium – A1

Question 5.
Write down the symbols for the following elements.
Antimony, Iron, Gold, Silver, Mercury, Lead, Sodium
Answer:
The symbols of given elements are as follows:

Antimony – Sb
Iron – Fe
Gold – Au
Silver – Ag
Mercury – Hg
Lead – Pb
Sodium – Na

Following are atomic masses of a few elements in Daltons and the molecular formulae of some compounds. Deduce the molecular masses of those compounds:

Atomic masses – H(l), 0(16), N(14), C(12), K(39), S(32) Ca(40), Na(23), Cl(35.5), Mg(24), Al(27)

Question 1.
Molecular formula – NaCl
Answer:
Molecular mass of NaCl (M)
= (Atomic mass of Na) x 1 + (Atomic mass of Cl) x 1
= (23 x 1) + (35.5 x 1)
= 23 + 35.5
= 58.5
∴ Molecular mass of NaCl (M) = 58.5

Question 2.
Molecular formula – MgCl₂
Answer:
Molecular mass of MgCl₂ (M)
= (Atomic mass of Mg) x 1 + (Atomic mass of Cl) x 2
= (24 x 1) + (35.5 x 2)
= 24 + 71
= 95
∴ Molecular mass of MgCl₂ (M) = 95?

Question 3.
Molecular formula – KNO₃
Answer:
Molecular mass of KNO₃ (M)
= (Atomic mass of K) x 1 + (Atomic mass of N) x 1 + (Atomic mass of O) x 3
= (39 x 1) + (14 x 1) + (16 x 3)
= 39 + 14 + 48
= 101
Molecular mass of KNO₃ (M) = 101

Question 4.
Molecular formula – H₂O₂
Answer:
Molecular mass of H₂O₂ (M)
= (Atomic mass of H) x 2 + (Atomic mass of O) x 2
= (1 x 2) + (16 x 2)
= 2 + 32
= 34
∴ Molecular mass of H₂O₂ (M) = 34.

Question 5.
Molecular formula – A1C1₃
Answer:
Molecular mass of A1C1₃ (M)
= (Atomic mass of Al) x 1 + (Atomic mass of Cl) x 3
= (27 x 1) + (35.5 x 3)
= 27 + 106.5
= 133.5
∴ Molecular mass of A1C1₃ (M) = 133.5

Question 6.
Molecular formula – Ca(OH)₂
Answer:
Molecular mass of Ca(OH)₂ (M)
= (Atomic mass of Ca) x 1 + (Atomic mass of O + Atomic Mass of H) x 2
= (40 x 1) + (16 + 1) x 2
= 40 + (17 x 2)
= 40 + 34
= 74
∴ Molecular mass of Ca(OH)₂ (M)
= 74

Question 7.
Molecular formula – MgO
Answer:
Molecular mass of MgO (M)
= (Atomic mass of Mg) x 1 + (Atomic mass of 0)xl
= (24 x 1) + (16 x 1)
= 24 + 16
= 40
Molecular mass of MgO (M) = 40

Question 8.
Molecular formula – H2S04
Answer:
Molecular mass of H2S04 (M)
= (Atomic mass of H) x 2 + (Atomic mass of S) x 1 + (Atomic mass of O) x 4
= (1 x 2) + (32xl) + (16×4)
= 2 + 32 + 64
= 98
Molecular mass of H2S04 (M) = 98

Question 9.
Molecular formula – HN03
Answer:
Molecular mass of HN03 (M)
= (Atomic mass of H) x 1 + (Atomic mass of N) x 1 + (Atomic mass of O) x 3
= (lxl)+ (14xl)+ (16×3)
= 1 + 14 + 48
= 63
Molecular mass of HNOs (M) = 63

Question 10.
Molecular formula – NaOH
Answer:
Molecular mass of NaOH (M)
= (Atomic mass of Na) x 1 + (Atomic mass of O) x 1 + (Atomic mass of H) x 1
= (23 x 1) + (16 x 1) + (l x l)
= 23 + 16 + 1
= 40
Molecular mass of NaOH (M) = 40

Question 11.
How many molecules of water are there in 36 g water?
Answer:
Given : Mass of water (H₂O) m = 36g
To find : Number of molecules in 36g of water
Solution :
Molecular mass of (H₂O) M = (Atomic mass of H) x 2 + (Atomic mass of O) x 1 Molecular mass of (H₂O) M
= (1 x 2) + 16 x 1
Molecular mass of (H₂O) M = 18
According to the formula,
Number of moles in the given H₂O (n)

1 mol of H₂O contains 6.022 x 10²³ molecules.
∴ 2 mol of H₂O contains 2 x 6.022 x 10²³ molecules.
= 12.044 x 10²³ molecules, that is 36g of H₂O contains 12.044 x 10²³ molecules of H₂O.
36 g of water contains 12.044 x 10²³ molecules of water.

Question 12.
How many molecules of H2S04 are there in a 49 g sample?
Answer:
Given : Mass of Sulphuric acid (H₂SO₄) m = 49g
To find : Number of molecules in 49g of H₂SO₄
Solution:
Molecular mass of (H₂SO₄) M = (Atomic mass of H) x 2 + (Atomic mass of S) x 1 + (Atomic mass of O) x 4
Molecular mass of (H₂SO₄)M = (1 x 2) + (32 x 1) + (16 x 4)
= 2 + 32 + 64
= 98.
According to the formula,
Number of moles in the given H₂SO₄ (n)

∴ 1 mol of H₂SO₄ contains 6.022 x 10²³ molecules.
∴ 0.5 mol of H₂SO₄contains 0.5 x 6.022 x 10²³ molecules.
= 3.011 x 10²³ molecules,
that is 49g of H₂SO₄ contains 3.011 x 10²³ molecules of H₂SO₄.
49 g of Sulphuric acid contains 3.011 x 10²³ molecules of H₂SO₄.

Question 13.
Fill the following tables.
Answer:

Question 14.
Complete the following chart.
Answer:

Question 15.
The relative atomic masses of some elements in the chart below are given. You have to find the relative atomic masses of the others.
Answer:

Question 16.
Classify the following radicals into simple radicals and composite radicals: (Use your brain power;
\(\begin{array}{l}
\mathrm{Ag}^{+}, \mathrm{Mg}^{2+}, \mathrm{Cl}^{-}, \mathrm{SO}_{4}^{2-}, \mathrm{Fe}^{2+}, \mathrm{ClO}_{3}^{-}, \mathrm{NH}_{4}^{+}, \mathrm{Br}^{-} \\
\mathrm{NO}_{3}^{-}, \mathrm{Na}^{+}, \mathrm{Cu}^{+}
\end{array}\)
Answer:

Simple radicals	Composite radicals
Ag⁺	\(\mathrm{SO}_{4}^{2-}\)
Mg²⁺	\(\mathrm{ClO}_{3}^{-}\)
Cl	\(\mathrm{NH}_{4}^{+}\)
Fe²⁺	\(\mathrm{NO}_{3}^{-}\)
Br^–
Na⁺
Cu⁺

Question 17.
Which are the basic radicals and which are the acidic radicals among the following?
\(\begin{array}{l}
\mathrm{Ag}^{+}, \mathrm{Cu}^{2+}, \mathrm{Cl}^{+}, \mathrm{I}, \mathrm{SO}_{4}^{2-}, \mathrm{Fe}^{3+}, \mathrm{Ca}^{2+}, \mathrm{NO}_{3} ; \mathrm{S}^{2}, \mathrm{NH}_{4}^{+} \\
\mathrm{K}^{+}, \mathrm{MnO}_{4}, \mathrm{Na}^{+}
\end{array}\)
Answer:

Basic Radical	Acidic Radical
(i)Ag⁺	(i) Cl^–
(ii) Cu²⁺	(ii) I^–
(iii) Fe³⁺	\(\text { (iii) } \mathrm{SO}_{4}^{2-}\)
(iv) Ca²⁺	\(\text { (iv) } \mathrm{NO}_{3}^{-}\)
Wnh;	\(\text { (v) } \mathrm{S}^{2-}\)
(vi) K⁺	\(\text { (vi) } \mathrm{MnO}_{4}^{-}\)
(vii) Na⁺

Give examples:

Question 1.
Make a list of elements in the monoatomic and in the diatomic molecular state. (Make a list and discuss;
Answer:

Elements in the monoatomic molecular state are: Helium (He), Neon (Ne), Argon (Ar), Sodium (Na), Copper (Cu),
Elements in the diatomic molecular state are:
Oxygen (O₂), Nitrogen (N₂), Hydrogen (H₂), Chlorine (Cl₂), Fluorine (F₂).

Problem-based questions

Answer the following questions:

Question 1.
Is it possible to weigh one molecule using a weighing balance?
Answer:
No, it is not possible to weigh one molecule using a weighing balance.

Question 2.
Will the number of molecules be the same in equal weights of different substances?
Answer:
No, the number of molecules will not be the same in equal weights of different substances.

Question 3.
If we want equal number of molecules of different substances, will it work to take equal weights of those substances.
Answer:
No, if we want equal number of molecules of different substances, it will not work to take equal weights of those substances.

Answer the following:

Question 1.
What is the Dalton’s atomic theory?
Answer:
Dalton’s Atomic theory-

All matter is made of atoms. Atoms are indivisible and indestructible.
All atoms of a given element are identical in mass and properties.
Compounds are formed by a combination of two or more different kinds of atoms.
A chemical reaction is a rearrangement of atoms.

Question 2.
How are compounds formed?
Answer:
Compounds are formed by a chemical combination of two or more different kinds of atoms.

Question 3.
What are the molecular formulae of salt, slaked lime, water, lime, limestone?
Answer:
The molecular formulae for
Salt – Sodium chloride – NaCl
Slaked lime – Calcium hydroxide Ca(OH)₂
Water – H₂O
Lime – Calcium oxide – CaO
Lime stone – Calcium carbonate – CaCO₃

Question 4.
From which experiments was it discovered that atoms have an internal structure? When?
Answer:

In 1911, Earnest Rutherford conducted a well known experiment called as ‘Gold foil experiment’.
From this experiment it was discovered that atoms have internal structure.

Question 5.
What are the two parts of an atom? What are they made up of?
Answer:
The two parts of atoms are nucleus and extra nuclear part. Nucleus is made up of positively charged protons and electrically neutral neutrons and the extra nuclear part is made up of negatively charged electrons revolving around the nucleus in different orbits.

Open-ended questions

Q.3. 2. Answer the following questions:

Question 1.
How will the compounds, MgCl₂ and CaO be formed from their elements?
Answer:
(1) Magnesium Chloride (MgCl₂)
Magnesium atom (Mg): Electronic configuration
\((2,8,2) \stackrel{-2 e^{-}}{\longrightarrow}\) Magnesium ion Mg²⁺ (2,8).
Chlorine atom (Cl). Electronic configuration \((2,8,7) \stackrel{+1 e^{-}}{\longrightarrow}\) Chloride ion Ch (2,8,8).
∴ Mg²⁺+ 2CT → MgCl₂ (Magnesium Chloride)

A Magnesium atom gives away 2e^– and a cation of Magnesium (Mg²⁺) is formed, hence, the valency of magnesium is two.
Two chlorine atoms takes le^– each and forms two anions of chlorine (2Cl^–) (chloride), and thus, the valency of chlorine is one.
After the give and take of electrons is over, the electronic configuration of all the resulting ions has a complete octet.
Due to the attraction between the unit but opposite charges on all the ions, one chemical bond known as ionic bond is formed between Mg²⁺ and 2C1^– each and the compound MgCl₂ is formed.

(2) Calcium Oxide (CaO)
Calcium atom (Ca): Electronic configuration
\((2,8,8,2) \stackrel{-2 e^{-}}{\longrightarrow}\) Calcium ion Ca²⁺ (2,8,8).
Oxygen atom (O). Electronic configuration (2,6)
\(\stackrel{+2 e^{-}}{\longrightarrow}\) Oxygen ion O^2- (2,8).
∴ Ca²⁺+ O^2- → CaO

A calcium atom gives away 2er and a cation of calcium (Ca²⁺) is formed, hence, the valency of calcium is two.
An oxygen atom takes 2e^– and forms anions of oxygen (O^2-) (oxide), and thus, the valency of oxygen is two.
After the give and take of electrons is over, the electronic configuration of both the resulting ions has a complete octet.
Due to the attraction between the unit but opposite charges on the two ions, one chemical bond known as ionic bond is formed between Ca²⁺ and O^2- and the compound CaO is formed.

Question 2.

Take 56 g calcium oxide in a large conical flask and put 18 g water in it.
Observe what happens.
Measure the mass of the substance formed.
What similarity do you find? Write your inference.

Answer:
(i) When 18 g of water is added to 56 g of calcium oxide, calcium oxide combines with water to form calcium hydroxide Ca(OH)₂

(ii) The mass of calcium hydroxide formed is 74 g.?

(iii) In this activity the total mass of reactants, Calcium oxide + Water = 56 g +18 g = 74 g.
It is equal to the mass of the product formed. Ca(OH)₂ = 74g.

This activity verifies the Law of Conservation of Matter, i.e., in a chemical reaction, the total weight of the reactants is same as the total weight of the products formed due to the chemical reactions.

Question 3.

Take a solution of calcium chloride in a conical flask and a solution of sodium sulphate in a test tube.
Tie a thread to the test tube and insert it in the conical flask.
Seal the conical flask with an airtight rubber cork.
Weigh the conical flask using a balance.
Now tilt the conical flask so that the solution in the test tube gets poured in the conical flask.
Now weigh the conical flask again.

Answer:

In this activity, a white precipitate of CaS04 in NaOl is seen in the conical flask after the reaction.
There is no change in the weight of the flask before and after the reaction.
This activity verifies the Law of Conservation of Matter i.e., in a chemical reaction, the total weight of the reactants is same as the total weight of the products formed due to the chemical reactions.

Question 4.
Using the chart of ions/radicals and the cross-multiplication method, write the chemical formulae of the following compounds : Calcium carbonate, Sodium bicarbonate, Silver chloride, Calcium hydroxide, Magnesium oxide, Ammonium phosphate, Cuprous bromide, Copper sulphate, Potassium nitrate, Sodium dichromate.

Answer:
Calcium carbonate – CaCO₃ Sodium bicarbonate – NaHCO₃ Silver chloride – AgCl, Calcium hydroxide – Ca(OH)₂, Magnesium oxide – MgO, Ammonium phosphate – (NH₄)₃PO₄, Cuprous bromide – CuBr, Copper sulphate – CuSO₄, Potassium nitrate – KNO₃, Sodium dichromate – Na₂Cr₂O₇.

Class 9 Science Chapter 3 Current Electricity Additional Important Questions and Answers

(A) Select the correct option:

Question 1.
The proportion by weight of hydrogen and oxygen in water is ……………………….. .
(a) 8 : 1
(b) 2 : 1
(c) 1 : 2
(d) 1 : 8
Answer:
(d) 1: 8

Question 2.
The proportion by weight of carbon and oxygen in carbon dioxide is ……………………….. .
(a) 8 : 3
(b) 3 : 8
(c) 3 : 2
(d) 2 : 3
Answer:
(b) 3 : 8

Question 3.
A nucleus of an atom is made up of positively charged ………………………… and electrically neutral ……………………….. .
(a) protons; neutrons
(b) electrons; neutrons
(c) neutrons; protons
(d) neutrons; electrons
Answer:
(a) protons; neutrons

Question 4.
The size of an atom is determined by its ……………………….. .
Answer:
radius

Question 5.
Atomic radius is expressed in ……………………….. .
(a) milimetres
(b) centimetres
(c) nanometres
(d) picometres
Answer:
(c) nanomet res

Question 6.
The atomic size depends on the number of ………………………… in the atom.
(a) protons
(b) nucleus
(c) neutrons
(d) electron orbits
Answer:
(d) electron orbits

Question 7.
The mass of an atom is concentrated in its ……………………….. .
(a) protons
(b) nucleus
(c) neutrons
(d) electrons
Answer:
(b) nucleus

Question 8.
The total number of protons and neutrons in the atomic nucleus is called the ……………………….. .
(a) atomic number
(b) electronic configuration
(c) atomic mass number
(d) valency
Answer:
(c) atomic mass number

Question 9.
A ………………………… is that quantity of a substance whose mass in grams is equal in magnitude to the molecular mass of that substance in Daltons.
(a) mole
(b) dalton
(c) dozen
(d) gross
Answer:
(a) Mole

Question 10.
Avogadro’s number is denoted by the symbol ……………………….. .
(a) N_G
(b) N_v
(c) N_A
(d) N_D
Answer:
(c) N_A

Question 11.
A mole of any substance stands for ………………………… molecules.
(a) 60.22 x 10²³
(b) 6.022 x 10²²
(c) 6.022 x 10²³
(d) 60.22 x 10²²
Answer:
(a) 60.22 x 10²³

Question 12.
The capacity of an element to combine is called its ……………………….. .
(a) valency
(b) electronic configuration
(c) atomic number
(d) volence electrons
Answer:
(a) valency

Question 13.
Electronic configuration of sodium atom is ……………………….. .
(a) (2, 8, 3)
(b) (2, 8, 7)
(c) (2, 8, 2)
(d) (2, 8,1)
Answer:
(d) (2,8,1)

Question 14.
Electronic configuration of chlorine atom is ……………………….. .
(a) (2, 8, 3)
(b) (2, 8, 7)
(c) (2, 8, 2)
(d) (2, 8, 1)
Answer:
(b) (2, 8, 7)

Question 15.
Positively charged ions are called as ……………………….. .
(a) cations
(b) anions
(c) nucleous
(d) protons
Answer:
(a) cations

Question 16.
Negatively charged ions are called as ……………………….. .
(a) cations
(b) anions
(c) nucleus
(d) electrons
Answer:
(b) anions

Question 17.
Iron (Fe) exhibits the variable valencies ……………………….. .
(a) 1 and 2
(b) 2 and 3
(c) 3 and 4
(d) 2 and 4
Answer:
(b) 2 and 3

Question 18.
Cationic radicals are called as ………………………… radicals.
(a) basic
(b) acidic
(c) neutral
(d) mixed
Answer:
(a) basic

Question 19.
Anionic radicals are called as ………………………… radicals.
(a) basic
(b) acidic
(c) neutral
(d) mixed
Answer:
(b) acidic

Question 20.
The unit Dalton is used to express …………………………
(a) atomic mass
(b) atomic radius
(c) atomic number
(d) mass number
Answer:
(a) atomic mass

Question 21.
The valency of element with electronic configuration ………………………… is 2.
(a) (2,5)
(b) (2, 4)
(c) (2, 6)
(d) (2, 7)
Answer:
(c) (2, 6)

Question 22.
The symbol of Avogadro’s number is ……………………….. .
(a) ND
(b) N0
(c) NB
(d) NA
Answer:
(d) NA

Question 23.
………………………. is bicarbonate radical.
\((a) \mathrm{HCO}_{3}^{2-} (b) \mathrm{CO}_{3}^{-}
(c) \mathrm{HCO}_{3}^{-}
(d) \mathrm{CO}_{3}^{2-}\)
Answer:
\(\text { (c) } \mathrm{HCO}_{3}^{-}\)

Question 24.
Molecular formula of sodium sulphate is ……………………….. .
(a) Na(SO₄)₂
(b) Na₂SO₄
(c)Na₂(SO₄)₂
(d)NaSO₄
Answer:
(b) Na₂SO₄

Question 25.
………………………… is a composite radical.
(a) Fe³⁺
(b) Ca²⁺
(c) NH₄⁺
(d) S^2-
Answer:
(c) NH

Question 26.
A mole of any substance stands for ………………………… molecules.
(a) 6.022 x 10²³
(b) 6.022 x 10²²
(c) 60.22 x 10²³
(d) 60.22 x 10²²
Answer:
(a) 6.022 x 10²³

Question 27.
The mass of an atom is concentrated in its ………………………… .
(a) nucleus
(b) electrons
(c) extranuclear part
(d) protons
Answer:
(a) nucleus

Question 28.
………………………… g of water make 1 mole of water.
(a) 32
(b) 33
(c) 16
(d) 18
Answer:
(d) 18

Complete the analogy:

(1) Electron : extra nuclear part:: Neutron ………………………… .
(2) Sodium: (2, 8, 1):: Chlorine:: ………………………… .
(3) K : basic radical :: Br^– : ………………………… .
(4) Cut: simple radical:: NH₄⁺: ………………………… .
(5) Sodium sulphate: Na₂SO₄:: Potassium Sulphate: ………………………… .
(6) Mercurous: Hg⁺:: Mercuric : ………………………… .
(7) Positively charged ion : cation:: Negatively charged ion : ………………………… .
(8) 12: 1 dozen :: 144 : ………………………… .
(9) Hydrogen : \(\odot\) :: Copper : ………………………… .
(10) Law of constant proportions : J. L. Proust::
Law of conservation of matter : ………………………… .
Answer:
(1) nucleus
(2) (2, 8, 7)
(3) acidic radical
(4) composite radical
(5) K₂SO₄
(6) Hg²⁺
(7) anion
(8) 1 gross
(9) ©
(10) Antoine Lavoisier.

Match the columns:

Column A’	Column ‘B’
Example	Atomic radius (in metres)
(1) Water molecule (2) Haemoglobin molecule (3) Hydrogen atom	(a) 10^-10(b) 10^-9(c) 10^-8

Answer:
(1-b),
(2- c),
(3 – a)

Column ‘A’	Column ‘B’
Element	Atomic mass
(1) Neon	(a) 35.5
(2) Silicon	(b) 32
(3) Chlorine	(c) 28
(4) Sulphur	(d) 20

Answer:
(1 – d),
(2 – c),
(3 – a),
(4 – b)

Column ‘A’	Column ‘B’
Molecule	Molecular mass in grams
(1) h₂	(a) 32 g
(2) H₂O	(b) 34 g
(3) O₂	(c) 2 g
(4) H₂O₂	(d) 18 g

Answer:
(1 – c),
(2 – d),
(3 – a),
(4 – b)

Column ‘A’	Column B’
Radicals	Names
(1) \(\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}\)	(a) Carbonate
(2) \(\mathrm{ClO}_{3}^{-}\)	(b) Chromate
(3) \(\mathrm{CO}_{3}^{2-}\)	(c) Dichromate
(4) \(\mathrm{CrO}_{4}^{2-}\)	(d) Chlorate

Answer:
(1 – c),
(2 – d),
(3 – a),
(4 – b)

Answer the following in one sentence:

Question 1.
What are valence electrons?
Answer:
The electrons present in the outermost orbit of an atom are called valence electrons.

Question 2.
Give the formula to determine the number of moles of a substance.
Answer:
The formula to determine the number of moles of a substance is as given below.

Question 3.
What are basic radicals? Give examples.
Answer:
The radicals which are formed by removal of electrons from the atoms of metals are called as basic radicals, e.g., Na+, Cu2+

Question 4.
What are acidic radicals? Give examples.
Answer:
The radicals which are formed by adding electrons to the atoms of non-metals are called as acidic radicals, e.g., CT, S2-

State whether the following statement is ‘True’ or ‘False’. Correct the false statement.

(1) Molecular state of oxygen is monoatomic.
(2) The capacity of an element to combine is called its valency.
(3) Anionic radicals are basic radicals.
(4) The magnitude of charge on any radical is its atomic number.
(5) In a chemical reaction, mass of original matter and mass of matter newly formed as a result of chemical change are equal.
(6) The proportion by weight of carbon and oxygen in carbon dioxide is 3 : 5.
(7) Relative mass of hydrogen is 1.
(8) The number of molecules in a given quantity of a substance is determined by its atomic mass.
(9) Avogadro’s number is 6.022 x 10²³
(10) Valency of sodium is 2.
Answer:
(1) False. Molecular state of oxygen is diatomic:
(2) True
(3) False. Anionic radicals are acidic radicals.
(4) False. Magnitude of charge on any radical is its valency.
(5) True
(6) False. The proportion by weight of carbon and oxygen in carbon dioxide is 3 : 8.
(7) True
(8) False. The number of molecules in a given quantity of a substance is determined by its molecular mass.
(9) True
(10) False. Valency of sodium is 1.

Name the following:

Question 1.
Scientist who gave Law of Conservation of Matter.
Answer:
Antoine Lavoisier

Question 2.
Scientist who gave Law of Constant Proportion.
Answer:
J. L. Proust

Question 3.
What are protons and neutrons present in nucleus together called as?
Answer:
Nucleons

Question 4.
Unit used to express atomic radius.
Answer:
Nanometre

Question 5.
The number (p + n) in the atomic nucleus is called as?
Answer:
Atomic mass number

Question 6.
Name the unit of atomic mass.
Answer:
Dalton (u)

Question 7.
Write molecular formula of two ionic compounds containing chlorine.
Answer:
NaCl, MgCl₂

Question 8.
Give two monoatomic radicals.
Answer:
Na⁺, Cl^–

Question 9.
Give two examples of simple radicals.
Answer:
Ag⁺, O^2-

Give scientific reasons:

Question 1.
An atom is electrically neutral though it contains charged particles.
Answer:

An atom is made up of a nucleus and an extranuclear part. Protons and neutrons are present in the nucleus.
The nucleus is positively charged. The extranuclear part is made up of negatively charged electrons.
Protons are positively charged, electrons are negatively charged and neutrons are without any charge.
The magnitude of their charges is the same when they are equal in number.
Hence, the negative charge on all the extra, nuclear electrons together balances the positive charge on the
nucleus.
Therefore, an atom is electrically neutral though it contains charged particles.

Question 2.
Neon is chemically inert element.
Answer:

Atomic number of neon is 10, so its electronic configuration is (2, 8). There are 8 electrons in its 2nd shell, fulfilling its capacity.
Thus, neon has a complete octet.
It has a stable orbit therefore, it does not indulge in chemical reactions. Hence, neon is a chemically inert element.

Question 3.
The valency of sodium (Na) is one.
Answer:

The electronic configuration of sodium (Na) is (2, 8,1). It has 1 electron in its 3rd orbit.
It tends to give up this electron so that it is left up with (2, 8), having 8 electrons in the second orbit, with a stable state.
The loss of one electron leads to the formation of sodium ion (Na+) which is positively charged as it has lost one electron.

Question 4.
The valency of chlorine (Cl) is one.
Answer:

The electronic configuration of chlorine (Cl) is (2, 8, 7). It has 7 electrons in its 3rd orbit.
It tends to take one electron from another atom so that it has 8 electrons in the outermost orbit with electronic configuration (2,8,8) with stable state.
The gaining of one electron leads to formation of chloride ion (Cl^–) which is negatively charged as it has gained one electron.

Question 5.
The valency of Magnesium (Mg) is two.
Answer:

The electronic configuration of Magnesium (Mg) is (2,8,2), it has 2 electrons in its 3rd orbit.
It tends to give these ‘2’ electrons so that it is left up with (2, 8), having 8 electrons in the second orbit, with a stable state.
The loss of two electrons leads to the formation of Magnesium ion (Mg2+) which is double positively charged as it has lost two electrons.

Question 6.
Valency is always a whole number.
Answer:

The number of electrons that an atom of an element gives away, takes up or shares forming a bond is called the valency of that element.
These electrons are always in whole numbers and not in fractions.
Therefore, valency is always a whole number.

Question 7.
Atomic size of potassium is bigger than atomic size of sodium.
Answer:

The atomic size of an element depends on the number of electron orbits in the atom of that element.
The greater the number of orbits, the larger the size.
Atomic number of potassium (K) is 19. Hence, its electronic configuration is (2, 8, 8,1). While atomic number of sodium (Na) is 11. Hence its electronic configuration is (2, 8,1)
Number of orbits in potassium atom is 4, while that in sodium atom is 3.
Hence, atomic size of potassium is bigger than atomic size of sodium.

Question 8.
The atomic size of sodium is bigger than atomic size of Magnesium.
Answer:

The atomic size of an element depends on the number of electron orbits in the atom of that element.
If 2 atoms have the same outermost orbit, then the atom having the larger number of electrons in the outermost orbit is smaller than the one having fewer electrons in the same outermost orbit.
Atomic number of sodium (Na) is 11. Hence, its electronic configuration is (2, 8, 1) while atomic number of magnesum (Mg) is 12 and hence its electronic configuration is (2, 8, 2).
As compared to sodium atom Magnesum atom has larger number of electrons n its electronic configuration.
Therefore, atomic size of sodium is bigger than atomic size of Magnesium.

Write the names of the following compounds and deduce their molecular masses:

Atomic masses : H(1), 0(16), N(14), C(12), K(39), S(32), Ca(40), Na(23), C1(35.5), Mg(24), A1(27), P(31)

Question 1.
Molecular mass of K₂CO₃Answer:

Question 2.
Molecular mass of CO₂Answer:

Question 3.
Molecular mass of MgCl₂Answer:

Question 4.
Molecular mass of NaOH
Answer:

Question 5.
Molecular mass of AIPO₄Answer:

Question 6.
Molecular mass of NaHCO₃Answer:

Numerical.

Question 1.
Magnesium Oxide:
Answer:
Given : Number of moles of Magnesium oxide (MgO)n = 0.2 mol
To find : Mass in grams of 0.2 mol of MgO
Solution:
Molecular mass of (MgO)M
= (Atomic mass of Mg) x 1 + (Atomic mass of O) x 1
= 24 x 1 + 16 x 1
= 24 + 16
Molecular mass of (MgO)M = 40
According to the formula Number of moles in the given MgO (n)

Mass of MgO in grams (m) = 0.2 x 40
Mass of MgO in grams (m) = 8 g.
Mass of 0.2 mole of MgO is 8 g

Question 2.
Calcium Carbonate:
Answer:
Given : Number of moles of Calcium carbonate (CaCO₃) n = 0.2 mol
To find : Mass in grams of 0.2 mol of CaCO₃
Solution:
Molecular mass of (CaCO₃) M
= (Atomic mass of Ca) x 1 + (Atomic mass of C) x 1 + (Atomic mass of O) x 3
= (40 x l) + (12 x 1) +(16 x 3)
= 40+ 12+ 48
Molecular mass of (CaCO₃) M = 100
According to the formula Number of moles in the given CaCO₃ (n)

∴ Mass of CaCO₃ in grams (m) = 0.2 x 100
∴ Mass of CaCO₃ in grams (m) = 20 g
Mass of 0.2 mole of CaCO₃ is 20 g

State laws/Define the following:

Question 1.
Law of Conservation of Matter.
Answer:
In a chemical reaction, the total weight of the reactants is same as the total weight of the products formed due to chemical reaction.

Question 2.
Law of Constant Proportion.
Answer:
The proportion by weight of the constituent elements in the various samples of a compound is fixed.

Question 3.
Molecular Mass:
Answer:
The molecular mass of a substance is the sum of the atomic masses of all the atoms in a single molecule of that substance.

Question 4.
Mole
Answer:
A mole is that quantity of a substance whose mass in grams is equal in magnitude to the molecular mass of that substance in Daltons.

Question 5.
Valency
Answer:
The capacity of an element to combine is called its valency.

Question 6.
Electronic definition of Valency
Answer:
The number of electrons that an atom of an element gives away or takes up while forming an ionic bond is called valency of that element.

Question 7.
Radicals
Answer:
The positively or negatively charged ions that take part independently in chemical reactions are called radicals.

Question 8.
Atomic size determination
Answer:
The size of an atom is determined by its radius. The atomic radius of an isolated atom is the distance between the nucleus of an atom and its outermost orbit.

Question 9.
Atomic mass number
Answer:
The number of protons and neutrons in the atomic nucleus is called the atomic mass number.

Question 10.
Unified mass
Answer:
Unified mass is the standard unit of atomic mass that quantifies mass on an atomic or molecular scale. Its symbol is ‘u’.
1 u = 1.66053904 x 10^-27 kg.

Question 11.
Molecular mass of a substance
Answer:
The molecular mass of a substance is the sum of the atomic masses of all the atoms in a single molecule of that substance. Like atomic mass, molecular mass is also expressed in the unit Dalton (u).

Answer the following questions:

Question 1.
What is variable valency?
Answer:

Under different conditions, the atoms of some elements give away or take up a different number of electrons.
In such cases, those elements exhibit more than one valency.
This property of elements is called variable valency.

Complete the following table:

Question 1.
Write down the cations and anions obtained from the compounds in the following chart.
Answer:

Answer the following questions:

Question 1.
Using the chart of ions/radicals and the cross-multiplication method, write the chemical formulae of the following compounds:

(a) Calcium carbonate
Answer:

∴ Chemical formula of Calcium carbonate is CaCO₃

(b) Sodium bicarbonate
Answer:

∴ Chemical formula of Sodium bicarbonate is NaHCO₃

(d) Calcium hydroxide Answer: Symbol Ca OH
Answer:

∴ Chemical formula of Calcium hydroxide is Ca(OH)₂

(e) Magnesium oxide
Answer:

∴ Chemical formula of Magnesium oxide is MgO

(f) Ammonium phosphate
Answer:

∴ Chemical formula of Ammonium phosphate is (NH₄)₃PO₄

(g) Cuprous bromide
Answer:

∴ Chemical formula of Cuprous bromide is CuBr.

(h) Copper sulphate
Answer:

∴ Chemical formula of Copper sulphate is CuSO₄.

(i) Potassium nitrate
Answer:

∴ Chemical formula of Potassium nitrate is KNO₃.

(j) Sodium dichromate
Answer:

∴ Chemical formula of Sodium dichromate is Na₂Cr₂O₇.

9th Std Science Questions And Answers:

Reflection of Light Class 9 Science Chapter 11 Questions And Answers Maharashtra Board

January 6, 2025January 5, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Science Solutions Chapter 11 Reflection of Light Notes, Textbook Exercise Important Questions and Answers.

Std 9 Science Chapter 11 Reflection of Light Question Answer Maharashtra Board

Class 9 Science Chapter 11 Reflection of Light Question Answer Maharashtra Board

1. Answer the following questions.

a. Explain the difference between a plane mirror, a concave mirror and a convex mirror with respect to the type and size of the images produced.
Answer:

	Plane mirror	Concave mirror	Convex mirror
Type of image	Virtual and Erect	Virtual (erect) as well as Real (inverted)	Virtual and Erect
Size of image	Same size	Diminished, Same size and magnified	Diminished

b. Describe the positions of the source of light with respect to a concave mirror in
1. Torch light
2. Projector lamp
3. Floodlight
Answer:
(a) Torch light: The source of light is placed at the focus.
(b) Projector lamp : The source of light is placed at the centre of curvature.
(c) Flood light : The source of light is placed just beyond the centre of curvature.

c. Why are concave mirrors used in solar devices?
Answer:

Solar devices like solar cooker or solar water heater use solar energy to cook food or heat water.
When sun rays fall on the concave mirror, they converge and come together in the focal plane.
Due to convergence, the intensity of sun rays increases and the food or water is heated faster. Hence, concave mirrors are used in solar- devices.

d. Why are the mirrors fitted on the outside of cars convex?
Answer:

A convex mirror is used as rear view mirror because they form erect, virtual, and diminished images.
This, allows the driver to view a large area in a small mirror.

e. Why does obtaining the image of the sun on a paper with the help of a concave mirror burn the paper?
Answer:

When sunrays fall on the concave mirror, they converge and come together in the focal plane.
Due to convergence, the intensity of sunrays increases.
Hence, image of the sun on a paper with the help of concave mirror bums the paper.

f. If a spherical mirror breaks, what type of mirrors are the individual pieces?
Answer:

When a spherical mirror breaks into smaller pieces, the radius of curvature and focal length does not change.
Hence, it will continue to behave like a spherical mirror only.

2. What sign conventions are used for reflection from a spherical mirror?
Answer:
According to the Cartesian sign convention, the pole of the mirror is taken as the origin. The principal axis is taken as the X-axis of the frame of reference. The sign conventions are as follows.

The object is always kept on the left of the mirror. All distances parallel to the principal axis are measured from the pole of the mirror.
All distances measured towards the right of the pole are taken to be positive, while those measured towards the left are taken to be negative.
The distance measured vertically upwards from the principal axis are taken to be positive.
The distance measured vertically downwards from the principal axis are taken to be negative.
The focal length of a concave mirror is negative while that of a convex mirror is positive.

3. Draw ray diagrams for the cases of images obtained in concave mirrors as described in the table on page 122.

Answer:
(a) A ray diagram for object at infinity for a concave mirror.

Image position	Nature of image
At focus	Real, inverted and point image

(b) A ray diagram for object beyond centre of curvature for a concave mirror.

An object beyond centre of curvature for a concave mirror

Image position	Nature of image
Between the centre of curvature and focus.	Real, inverted and diminished.

(c) A ray diagram for object at the centre of curvature for a concave mirror.

Object at centre of Curva fu re be a concave mirror.

Image position	Nature of image
At the centre of curvature.	Real, inverted and same size

(d) A ray diagram for object between F and C for a concave mirror.

Object between F & C for a concave mirror

Image position	Nature of image
Beyond the centre of curvature.	Real, inverted and magnified.

(e) A ray diagram for obj ect at focus for a concave mirror.

Object at focus for a concave mirror.

Image position	Nature of image
At infinity.	Real, inverted and highly magnified.

(f) A ray diagram for object between pole and focus for a concave mirror.

Image position	Nature of image
Behind the mirror.	Virtual, erect and magnified.

4. Which type of mirrors are used in the following?
Periscope, floodlights, shaving mirror, kaleidoscope, street lights, headlamps of a car.

Answer:

Objects	Type of Mirror
Periscope	Plane mirror
Floodlights	Concave mirror
Shaving mirror	Concave mirror
Kaleidoscope	Plane mirror
Street lights	Convex mirror
Head lamps of car	Concave mirror

5. Solve the following examples

a. An object of height 7 cm is kept at a distance of 25 cm in front of a concave mirror. The focal length of the mirror is 15 cm. At what distance from the mirror should a screen be kept so as to get a clear image? What will be the size and nature of the image?
Solution:
Given: Object size (h₁) = 7 cm
Object distance (u) = -25 cm
Focal length (f) = -15cm
To find: Image distance (u) = ?
Image size (h₂) = ?

The screen should be kept 373 cm in front of the mirror. The image is real.

The height of the image is 10.5 cm, it is an inverted and enlarged image.

b. A convex mirror has a focal length of 18 cm. The image of an object kept in front of the mirror is half the height of the object. What is the distance of the object from the mirror?
Solution:
Given: Image size (h₂) = ¹/₂h₁
Focal length (f) = 18 cm
To find: Object distance (u) ?

The object is placed in front of the convex mirror at a distance of 18 cm.

c. A 10 cm long stick is kept in front of a concave mirror having focal length of 10 cm in such a way that the end of the stick closest to the pole is at a distance of 20 cm. What will be the length of the image?
Solution:
Given: Object size (h₁) = 10 cm
Object distance (u) = -20 cm
Focal length (f) = -10 cm

The height of the image is 10 cm and it is a real and inverted image.

6. Three mirrors are created from a single sphere. Which of the following:
pole, centre of curvature, radius of curvature, principal axis – will be common to them and which will not be common?
Answer:

Centre of curvature and Radius of curvature will be common for all three pieces.
Pole and Principal axis will not be common.

Class 9 Science Chapter 11 Reflection of Light Intext Questions and Answers

Class 9 Science Chapter 11 Reflection Of Light Question 1.
What is light
Answer:
Light is a form of electromagnetic radiation that produces the sensation of vision.

9th Class Science Chapter 11 Reflection Of Light Exercise Question 2.
What is a mirror?
Answer:
A mirror is a reflecting surface which reflects light and creates clear images.

9th Class Science Chapter 11 Reflection Of Light Exercise Answer Question 3.
Principal Focus of Concave and Convex Mirror.
Answer:

Principal Focus of the Concave Mirror	Principal Focus of the Convex Mirror
(i) Incident rays which are parallel to the principal axis of a concave mirror, after reflection from the mirror, meet at a particular point in front of the mirror on the principal axis. This point (F) is called the principal focus of the concave mirror. (ii) It is formed in front of the mirror. (iii) Focus of concave mirror is real.	(i) Incident rays parallel to the principal axis, after reflection, appear to come from a particular point behind the mirror lying along the principal axis. This point is called the principal focus of the convex mirror. (ii) It is formed behind the mirror. (iii) Focus of convex mirror is virtual.

9th Class Science Chapter 11 Reflection Of Light Notes Question 4.
If we hold a page of a book in front of a mirror, we see laterally inverted letters in the mirror. Why does it happen?
Answer:

When we hold a page of a book in front of the mirror, the image of the words appear laterally inverted.
The image of every point of the word is formed behind the mirror at the same distance from the mirror
Because of this the left and right side of the image is interchanged.
Hence, if we hold a page of a book in front of a mirror, we see laterally inverted letters in the mirror.

11 Reflection Of Light Exercise Question 5.
Which letters of the English alphabet form images that look the same as the original letters?
Answer:
A, H, I, M, O, T, U, V, W, X, Y

9th Science Chapter 11 Reflection Of Light Exercise Question 6.
When a person stands in front of a plane mirror, how is the image formed? What is the nature of the image?
Answer:

The image of a person is formed from every point of the source, thereby forming an extended image of the whole source.
The image formed would be virtual, upright and left-right reversed.

Answer the following questions:

Reflection Of Light Class 9 Questions And Answers Question 1.
Place two plane mirrors at an angle of 90a to each other. Place a small object between them. Images will be formed in both mirrors. How many images do you see? Now change the angle between the mirrors as given in the following table and count the number of images each time. How is this number related to the measure of the angle?
Answer:
The Relation between the angle between the mirrors and the number of images formed is given by
\(n=\frac{360^{\circ}}{\mathrm{A}}-1\)
n = number of images,
A = angle between the mirrors

Angle	Number of images
120°	2
90^s	3
60®	5
45®	7
30®	11

Class 9 Science Chapter 11 Reflection of Light Additional Important Questions and Answers

Can you recall?

9th Class Science Chapter 11 Reflection Of Light Question 1.
What is meant by reflection of light and what are the types of reflection?
Answer:
The bouncing back of light when it hits an opaque surface is called reflection of light. The two types of reflection are regular and irregular reflection.

Reflection Of Light Class 9 Exercise Answers Question 2.
What are the laws of reflection.
Answer:

The incident ray, reflected ray and normal all lie in the same plane at the point of incidence.
The angle of incidence is equal to the angle of reflection.
The incident ray and the reflected ray lie on opposite sides of the normal.

Choose and the correct option:

Class 9th Science Chapter 11 Reflection Of Light Question Answer Question 1.
If the reflected rays do not actually meet, such an image is called as image.
(a) real
(b) virtual
(c) magnified
(d) inverted
Answer:
(b) virtual

Class 9 Science Chapter 11 Reflection Of Light Exercise Solutions Question 2.
In a plane mirror, the perpendicular distance of the image from the mirror is equal to
(a) the perpendicular distance of the source from the object.
(b) the perpendicular distance of the source from the mirror.
(c) the parallel distance of the source from the object.
(d) the parallel distance of the source from the mirror.
Answer:
(b) the perpendicular distance of the source from the mirror

Reflection Of Light Class 9 Notes Pdf Maharashtra Board Question 3.
The image formed in a convex mirror is always
(a) virtual, smaller and behind the mirror
(b) virtual, smaller and in front of the mirror
(c) real, smaller and behind the mirror
(d) real, smaller and in front of the mirror
Answer:
(a) virtual, smaller and behind the mirror

Reflection Of Light Class 9 Solutions Question 4.
images can be displayed on a screen.
(a) Virtual
(b) Real
(c) Virtual and erect
(d) Virtual and inverted
Answer:
(b) Real

9th Class Science Chapter 11 Reflection Of Light Exercise Pdf Question 5.
A concave mirror is also called as a mirror.
(a) converging
(b) diverging
(c) plane
(d) outward curved
Answer:
(a) converging

9th Science Chapter 11 Reflection Of Light Question 6.
The centre of the mirror surface is called its
(a) pole
(b) centre of curvature
(c) principal axis
(d) focus
Answer:
(a) pole

Class 9 Science Chapter 11 Question Answer Reflection Of Light Question 7.
According to the new sign convention, the of the mirror is taken as origin.
(a) focus
(b) pole
(c) optical centre
(d) centre of curvature
Answer:
(b) pole

Class 9 Science Chapter 11 Reflection Of Light Exercise Question 8.
A convex mirror is also called as a mirror.
(a) converging
(b) plane
(c) diverging
(d) inward curved
Answer:
(c) diverging

Reflection Of Light Class 9 Maharashtra Board Question 9.
In order to see the full image of a person standing in front of a mirror, the minimum height of the mirror must be
(a) same height as that of the person
(b) double the height of the person
(c) half the height of the person
(d) quarter the height of the person
Answer:
(c) half the height of the person

Reflection Of Light Exercise 9th Class Question 10.
If the inner surface of the spherical mirror is reflecting, then it is a mirror, and if the outer surface is reflecting then it is mirror.
(a) convex, concave
(b) convex, plane
(c) concave, plane
(d) concave, convex
Answer:
(d) concave, convex

9th Std Science Chapter 11 Reflection Of Light Question 11.
The image formed by a concave mirror is
(a) always virtual and erect
(b) always virtual and inverted
(c) virtual if the object is placed between the pole and the focus
(d) virtual if the object is beyond the focus
Answer:
(c) virtual if the object is placed between the pole and the focus

Question 12.
No matter how far you stand from a spherical mirror, your image appears erect. The mirror may be
(a) plane
(b) concave
(c) convex
(d) either plane or convex
Answer:
(d) either plane or convex

Question 13.
In case of a concave mirror, an erect image is
(a) real and enlarged
(b) real and diminished
(c) virtual and diminished
(d) virtual and enlarged
Answer:
(d) virtual and enlarged

Question 14.
A rear view mirror of a car is
(a) plane mirror
(b) concave mirror
(c) convex mirror
(d) cylindrical mirror
Answer:
(c) convex mirror

Question 15.
An image of an object placed at infinite distance from a concave mirror is formed at
(a) the focus of the mirror
(b) behind the mirror
(c) centre of curvature
(d) infinity
Answer:
(a) the focus of the mirror

Question 16.
A ray of light parallel to principal axis after reflection from concave mirror passes through
(a) centre of curvature
(b) focus
(c) pole
(d) optical centre
Answer:
(b) focus

Question 17.
The image made by a plane mirror is a image.
(a) real
(b) virtual
(c) inverted
(d) diminished
Answer:
(b) virtual

Question 18.
The size of the image of an object placed at the focus of a concave mirror is
(a) erect
(b) very large
(c) same size
(d) diminished
Answer:
(b) very large

Question 19.
For virtual images, the height is while for real images, it is
(a) positive, positive
(b) negative, positive
(c) negative, negative
(d) positive, negative
Answer:
(d) positive, negative

Find the odd man out:

Question 1.
Torches, flood lights, head lamps of vehicles, rear view mirror.
Answer:
Rear view mirror – In rear view mirrors, convex . mirror is used. Concave mirrors are used in the rest.

Question 2.
Side mirrors of cars, parking mirrors, flood lights, mirror fitted in shops.
Answer:
Flood lights – In flood lights concave mirror is used. Convex mirrors are used in the rest.

Question 3.
Virtual and enlarged, virtual and diminished, real and inverted, real and magnified
Answer:
Virtual and diminished type of image is not formed by a concave mirror. All the other types of images are formed by a concave mirror.

Question 4.
Image is laterally inverted, image is of same size, image is at same distance, image is diminished.
Answer:
Image is diminished is not a characteristic of image formed in a plane mirror. Rest of them are characteristics of plane mirror.

Answer the following in one sentence:

Question 1.
What kind of mirror will a doctor use to concentrate on teeth, eyes, ears etc.?
Answer:
The doctor will use a concave mirror to concentrate on teeth, eyes, ears etc.

Question 2.
What do the nature, position and size of the image depend on?
Answer:
The nature, position and size of the image depend upon the distance of the object from the reflecting surface.

Question 3.
Give the expression for mirror formula.
Answer:
\(\frac{1}{v}+\frac{1}{u}=\frac{1}{f}\)

Question 4.
State any four uses of concave mirror.
Answer:
Concave mirrors are used in torches, headlights, shaving mirrors, dentists’ mirrors, solar devices etc.

Question 5.
What are the two types of spherical mirror?
Answer:
Convex mirror and concave mirror are the two types of spherical mirror.

Match the columns:

Question 1.

Column ‘A’	Column ‘B’
(1) Plane mirror	(a) Rear view mirror
(2) Concave mirror	(b) At laughing gallery
(3) Convex mirror	(c) At a hair dresser
(4) Irregular curved mirror	(d) At a dentist

Answer:
(1 – c),
(2 – d),
(3 – a),
(4 – b)

Question 2.

Column ‘A’	Column ‘B’
(1) Plane mirror	(a) Virtual and diminished image
(2) Concave mirror	(b) Virtual and same size image
(3) Convex mirror	(c) Real and inverted image

Answer:
(1 – b),
(2 – c),
(3 – a)

State whether the following statements are true or false. Correct the false statements:

(1) If the mirrors are kept at right angle to each other, then the number of images formed will be 4.
(2) A convex mirror is used in flood lights.
(3) A concave mirror always forms a magnified image.
(4) Images formed by convex mirrors are always virtual.
(5) The distance between the focus and the pole is called the radius of curvature.
(6) Reflection from a spherical mirror obeys laws of reflection.
(7) The reflecting surface of a concave mirror is curved.
(8) Distances measured in the direction of the incident light are taken as positive.
(9) If the image is erect, the height of the image is negative.
(10) A real image can be displayed on a screen.
(11) A concave mirror always forms a real and inverted image.
(12) Doctors use diverging beam of light to study teeth, ears and eyes.
Answer:
(1) False. if the mirrors are kept at right angle to each other then the number of images formed will be 3.
(2) False. a concave mirror is used in flood lights.
(3) False. a concave mirror can sometimes form a diminished image as well.
(4) True
(5) False. the distance between the focus and the pole is called the focal length.
(6) True
(7) True
(8) True
(9) False. if the image is erect, the height of the image is positive.
(10) True
(11) False. a concave mirror can also form a virtual and erect image.
(12) False. doctors use a converging beam of light to study teeth, ears and eyes.

Give scientific reasons:

Question 1.
A concave mirror is called a converging mirror.
Answer:

When rays of light parallel to the principal axis are incident on concave mirror, they converge.
After convergence, they meet at one point on the principal axis, hence concave mirror is called converging mirror.

Question 2.
Concave mirrors are used in torches and in car headlights.
Answer:

Concave mirrors are used in torches and car headlights because when a source of light is placed at the focus of a concave mirror, a parallel beam of light rays is obtained.
This helps us to see things upto a considerable distance in the darkness.

Question 3.
A dentist uses a concave mirror while examining teeth.
Answer:

A concave mirror produces an erect, virtual and magnified image of an object placed between its pole and focus.
A dentist uses this principle to get a clear and distinct image of teeth, hence, a dentist uses a concave mirror.

Solve the following numerlcals.

Tips for solving numerical:

Object distance (u) is always -ve
If Image distance (u) is +ve then image is behind the mirror and virtual. if u is -ve then image is in front of the mirror and real.
Object height (h₁) is always +ve since it is erect.
Image height (h₂) can be +ve for virtual and -ve for real.

Type – A

Question 1.
A bird is sitting in front of two plane mirrors inclined at an angle of 600 to each other. How many images does the bird see in the mirror?
Solution:
Given : Angle between mirror A = 60⁰
To find: Number of images formed n = ?

The brrd sees 5 images in the mirror.

Question 2.
A coin is kept in front of two plane mirrors inclined to each other. If 3 images of the coin are seen then what is the angle A between the mirrors?
Solution:
Given: no. of images formed n =3
To find: Angle between mirror A =?

The mirrors are inclined atan angle of 900 to each other.

Question 3.
An image is formed 5 cm behind a convex mirror of focal length 10 cm. At what distance is the object placed from the mirror?
Solution:
Given: Image distance (u) = 5 cm
Focal length (f) = 10 an
To find: Object distance (u) = ?

The object is placed at a distance of 10 cm in front of the mirror.

Question 4.
An object placed 20 cm in front of a convex mirror is found to have an image 15cm behind the mirror. Find the focal length of the mirror.
Solution:
Given: Object distance (u) = -20 cm
Image distance (u) = 15 cm
To find: focal length (f) = ?

The focal length of the convex mirror is 60 cm.

Numerical For Practice

Question 5.
An object is placed at a distance of 36 cm from a concave mirror of focal length 12 cm. Find the image distance.
Answer:
-18 cm

Question 6.
An arrow is placed at a distance of 25 cm from a diverging mirror of focal length 20 cm. Find the image distance.
Answer:
11.1 cm

Type – B

Question 1.
An object 4cm in height is placed at a distance of 36 cm from a concave mirror. The image is formed 18 cm in the front of the mirror. Find the height of the image.
Solution:
Given: Object height (h₁) = 4 cm
Image distance (u) = -18 cm
Object distance (u) = -36 cm
To find: Height of image (h₂) = ?

The height of the image is 2 cm and it is inverted.

Question 2.
An object 2 cm high is placed at a distance of 16cm from a concave mirror which produces a real image 3 cm high. Find the image distance.
Solution:
Given: Object height (h₁) = 2 cm
Object distance (u) = -16 cm
Image height (h₂) = -3 cm
To find: Image distance (u) = ?

The image is formed at a distance of 24 cm in front of the mirror.

Numericals For Practice

Question 3.
An object 10cm in height is placed at a distance of 36 cm from a concave mirror. 1f the image is formed at a distance of 18 cm in front of the mirror, find the height of the image.
Answer:
-5cm

Question 4.
A converging mirror forms a real image of height 4 cm of an object of height 1 cm placed 20 cm away from the mirror. Find the image distance.
Answer:
-80cm

Type – C

Question 1.
Rajashree wants to get an inverted image of height 5 cm of an object kept at a distance of 30 cm from a concave mirror. The focal length of the mirror is 10 cm. At what distance from the mirror should she place the screen? What will be the type of the image, and what is the height of the object?
Solution:
Given:
Focal length = f = -10 cm,
Object distance = u = -30 cm
Height of the image = h₂ = 7 cm
To find: Height of the object = h₁ = ?
Image distance = u =?

Rajashree has to place the screen 15 cm to the left of the mirror.
Magnification formula

The height of the object is 10 cm. Thus, the image will be real and diminished.

Question 2.
A 10 cm long stick is kept horizontally in front of the concave mirror having focal length of 10 cm in such a way that the end of the stick closest to the pole is at a distance of 20 cm. What will be the length of the image?
Solution:
The stick is kept parallel to the Principal axis. Distance between A and P is 20 cm. Say u₁ = 20 cm.
Hence, the other end of the stick is at distance, u₂ = (u₁ + 10) = 30 cm from pole of the mirror.

Using mirror formula for concave mirror,
Solution:

Here, negative signs indicate that images are formed on the left of the mirror.

The length of the image formed ?s given by, u = u₂ – u₁ = 15 – (-20) = 5cm.
The length of the image is 5 cm.

Numerical For Practice

Question 3.
An object 2 cm in height is placed at a distance of 16 cm from a concave mirror. If the focal length of the mirror is 9.6 cm., find the image distance, nature and size of the image.
Answer:
u = -24 an, h₂ = -3 cm; real, inverted and enlarged.

Question 4.
An arrow of 2.5cm height is placed at a distance of 25 cm from a diverging mirror of focal length 20 cm. Find the nature, position and size of the image formed.
Answer:
v = 11.1cm, h₁= 1.1cm; virtual and in dimirrished form.

Define the following:

Question 1.
Centre of curvature of mirror (C)
Ans.
The centre of the sphere of which the mirror is a parte is called the centre of curvature of the mirror.

Question 2.
The radius of curvature (R)
Answer:
The radius of the sphere of which the mirror is a part, is called the radius of curvature of the mirror.

Question 3.
Pole (P)
Answer:
The centre of the mirror surface is called its pole.

Question 4.
The principal axis of a mirror
Answer:
The straight line passing through the pole and centre of curvature of the mirror is called its principal axis.

Question 5.
The focus of a concave mirror (F)
Answer:
Incident rays which are parallel to the principal axis of a concave mirror, after reflection from the mirror, meet at a particular point in front of the mirror on the principal axis. This point (F) is called the principal focus of the concave mirror.

Question 6.
Focus of a convex mirror (F)
Answer:
Incident rays parallel to the principal axis, after reflection, appear to come from a particular point behind the mirror lying along the principal axis. This point is called the principal focus of the convex mirror.

Question 7.
Focal length of a mirror (f)
Answer:
The distance (f) between the pole and the principal focus of the mirror is called the focal length. This distance is half of the radius of curvature of the mirror. \(f=\frac{R}{2}\)

Answer the following in short:

Question 1.
What are the rules for drawing ray diagrams for the formation of image by spherical mirror?
Answer:
The rules are as follows :

If an incident ray is parallel to the principal axis, then the reflected ray passes through the principal focus.
If an incident ray passes through the principal focus of the mirror, the reflected ray is parallel to the principal axis.
If an incident ray passes through the centre of curvature of the mirror, the reflected ray traces the same path back.

Distinguish between:

Question 1.
Convex mirror and Concave mirror
Answer:

Convex mirror	Concave mirror
(i) In a convex mirror, the reflecting surface is on the outer side. (ii) It is called a diverging mirror. (iii) The focus of a convex mirror is virtual. (iv) It can form only a virtual image. (v) It can form only a diminished image.	(i) In a concave mirror, the reflecting surface is on the inner side. (ii) It is called a converging mirror. (iii) The focus of a concave mirror is real. (iv) It can form a real as well as a virtual image. (v) It can form an enlarged, diminished as well as the same size image.

Question 2.
Real image and Virtual image
Answer:

Real image	Virtual image
(i) A real image is formed only when the reflected rays actually meet at a point. (ii) Real images can be obtained on a screen. (iii) All real images are inverted.	(i) A virtual image is formed only when the reflected rays appear to meet at a point. (ii) Virtual images cannot be obtained on a screen. (iii) All virtual images are erect.

Answer the following questions:

Question 1.
If we keep the mirrors parallel to each other, how many images will we see ?
Answer:
When two mirrors are kept parallel to each other infinite images are formed, this is because light gets reflected infinite times.

Answer in detail:

Question 1.
What sign conventions are used for reflection from a spherical mirror?
Answer:

According to the Cartesian sign convention, the pole of the mirror is taken as the origin. The principal axis is taken as the X-axis of the frame of reference. The sign conventions are as follows.

The object is always kept on the left of the mirror. All distances parallel to the principal axis are measured from the pole of the mirror.
All distances measured towards the right of the pole are taken to be positive, while those measured towards the left are taken to be negative.
Distance measured vertically upwards from the principal axis are taken to be positive.
Distance measured vertically downwards from the principal axis are taken to be negative.
The focal length of a concave mirror is negative while that of a convex mirror is positive.

Question 2.
Draw ray diagrams for the image obtained in convex mirrors.
Answer:

Image position	Nature of image
Behind the mirror.	(A) Virtual, (B) Erect (C) Diminished

Question 3.
In order to see the full image of a person standing in front of a mirror, the minimum height of the mirror must be half the height of the person. Explain.
Answer:

Proof:

In the figure, the point at the top of the head, the eyes and a point at the feet of a person are indicated by H, E and F respectively.
R and S are midpoints of HE and EF respectively.
The mirror PQ is at a height of NQ from the ground and is perpendicular to it. PQ is the minimum height of the mirror in order to obtain the full image of the person.

For this, RP and QS must be perpendicular to the mirror.

Minimum height of the mirror
PQ = RS
= RE + ES
\(=\frac{\mathrm{HE}}{2}+\frac{\mathrm{EF}}{2}=\frac{\mathrm{HF}}{2}\)
= Half of the person’s height.

Question 4.
Determine the sign of magnification in each of the 6 cases in the table and verify that they are same using formulae
\(\mathbf{M}=\frac{h_{2}}{h_{1}}\) and \(\mathbf{M}=\frac{-v}{u}\)
Answer:

Question 5.
Explain the images formed by concave mirrors with respect to position of the image and object and also the Nature and size of image
Answer:

9th Std Science Questions And Answers:

Study of Sound Class 9 Science Chapter 12 Questions And Answers Maharashtra Board

January 6, 2025January 5, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Science Solutions Chapter 12 Study of Sound Notes, Textbook Exercise Important Questions and Answers.

Std 9 Science Chapter 12 Study of Sound Question Answer Maharashtra Board

Class 9 Science Chapter 12 Study of Sound Question Answer Maharashtra Board

1. Fill in the blanks and explain.

a. Sound does not travel through ……………………….……….. .
b The velocity of sound in steel is ……………………….………… than the velocity of sand in water.
c. The incidence of ……………………….………… in daily life shows that the velocity of sound is less than the velocity of light.
d. To discover a sunken ship or objects deep inside the sea, ……………………….………… technology is used.

2. Explain giving scientific reasons.

a. The roof of a movie theatre and a conference hall is curved.
Answer:

Sound waves get reflected from the walls and roof of a room multiple times. This causes a single sound to be heard not once but continuously. This is called reverberation.
Due to reverberation, some auditoriums or some particular seats in an auditorium have inferior sound reception. This can be compensated with curtains.
Ceilings of these halls are made curved so that sound after reflecting from the ceiling, reaches all parts of the hall and the quality of sound improves.

b. The intensity of reverberation is higher in a closed and empty house.
Answer:

Reverberation occurs due to multiple reflections of sound.
The furniture in the house acts as a sound-absorbing material.
So if the house is closed and empty, a reflection of sound will be maximum and hence, intensity of reverberation is higher.

c. We cannot hear the echo produced in a classroom.
Answer:

For distinct echoes, the minimum distance of the reflecting surface from the source of sound must be 17.2 m.
Benches in the classroom are sound absorbing materials which prevent echo of sound.
Because of these two reasons echo is not heard in a classroom.

3. Answer the following questions in your own words.

a. What is an echo? What factors are important to get a distinct echo?
Answer:

An echo is the repetition of the original sound because of reflection by some surface.
At 22°C, the velocity of sound in air is 344 m/s.
Our brain retains a sound for 0.1 seconds Thus, for us to be able to hear a distinct echo, the sound should take more than 0.1 seconds after starting from the source to get reflected and. come back to us.
We know that,
Distance = speed x time
= 344 m/s x 0.1 s
= 34.4 m
Thus, to be able to hear a distinct echo, the reflecting surface should be at a minimum distance of half of the above, i.e. 17.2 m.
As the velocity of sound depends on the temperature of air, this distance depends on the temperature.

b. Study the construction of the Golghumat at Vijapur and discuss the reasons for the multiple echoes produced there.
Answer:

Goighumat with a height of 51 metres and diameter of 37 metres with 3 metres thick walls is spread over approximately 1700 square metres.
This meets the conditions for echo i.e. : 17.2 metres minimum.
The dome of the golghumat is curved and hence, sound reflects multiple times before reaching the observer.
This is the reason for multiple echoes being produced.

c. What should be the dimensions and the shape of classrooms so that no echo can be produced there?
Answer:

Dimensions: The distance between opposite walls in a classroom must be less than 17.2 m so that the reflected sound returns to the observer within 0.1 s.
Shape: The classrooms should have curved ceilings and walls so that the reflected sound is directed towards the observer instantly within 0.1 s

4. Where and why are sound-absorbing materials used?
Answer:
The sound absorbing materials are used in :

School, cinema hall, concert hall, houses or places where quality of sound is important.
In the absence of sound absorbing material the sound will undergo multiple reflection causing reverberation of sound.

5. Solve the following examples.

a. The speed of sound in air at O °C is 332 m/s. If it increases at the rate of 0.6 m/s per degree, what will be the temperature when the velocity has increased to 344 m/s?
Answer:
Given:
Initial speed of sound at 0°C 332 m/s.
Final speed of sound -344 m/s.
Rate of increase per degree rise in temp. = 0.6m/s
To find:
Temperature when speed is 344m/s
Formulae:
Increase in temperature

Temperature when the speed of sound is 344 m/sis 20°C

b. Nita heard the sound of lightning after 4 seconds of seeing it. What was the distance of the lightning from her? (The velocity of sound in air is 340 m/s?)
Answer:
Given : Speed of sound (v) = 340 m/s
Time taken (f) = 4 sec
To find : Distance (s) = ?

The lightning has struck at a distance of 1360 m from the observer.

c. Sunil is standing between two walls. The wall closest to him is at a distance of 360 m. If he shouts, he hears the first echo after 4 s and another after another 2 seconds.
1. What is the velocity of sound in air?
2. What is the distance between the two walls? (Ans: 330 m/s; 1650 m)
Answer:
Given:
Distance of the closer wall (S₁) = 660 m
Time of echo from closer wall = 4 sec
∴ Time taken (t₁) = 4/2 sec = 2 sec
Time of echo from distant wall = 6 sec
∴ Time taken (t₂) = 6/2 sec = 3 sec
To find :
Velocity of sound in air (y) =?
Distance between two walls (S₁ + S₂) = ?

The velocity of sound in air is 330 mIs and the distance between two walls is 1650 m.

d. Hydrogen gas is filled in two identical bottles, A and B, at the same temperature. The mass of hydrogen in the two bottles is 12 gm and 48 gm respectively. In which bottle will sound travel faster? How may times as fast as the other? (Ans: In A; Twice)
Answer:
In A; Thrice

e. Helium gas is filled in two identical bottles A and B. The mass of the gas in the two bottles is 10 gm and 40 gm respectively. If the speed of sound is the same in both bottles, what conclusions will you draw? (Ans: Temperature of B is 4 times the temperature of A.)
Given:
Mass of Helium in bottle A = (mA) = 10gm
Mass of Helium in bottle B = (mB) = 40gm

The temperature of B is 4 times the temperature of A

Class 9 Science Chapter 12 Study of Sound Intext Questions and Answers

Study Of Sound Class 9 Notes Maharashtra Board Question 1.
How does the velocity of sound depend on its frequency?
Answer:
The velocity of sound is directly proportional to its frequency
ν = υ λ
when ν = velocity
υ = frequency
λ = wavelength

9th Class Science Chapter 12 Study Of Sound Exercise Question 2.
The molecular weight of oxygen gas (O₂) is 32 while that of hydrogen gas (H₂) is 2. Prove that under the same physical conditions, the velocity of sound in hydrogen is four times that in oxygen.
Answer:
Given:
Molecular wt of Oxygen (M_o) =32
Molecular wt of hydrogen (M_H) = 2
To Find:
V_H = 4 v_o

Hence, proved that velocity of sound in hydrogen is four times that in oxygen.

Answer the following:

Study Of Sound Class 9 Maharashtra Board Question 1.
How will you reduce reverberation in public halls or buildings?
Answer:
(i) Reverberation in public halls or buildings will be reduced by using sound absorbing materials like curtains on wall, carpets on the floor.
(ii) By keeping the windows open, as sound will not get reflected.

12 Study Of Sound 9th Class Exercise Question 2.
How is ultrasound used in medical science?
Answer:

Sonography: Sonography technology uses ultrasonic sound waves to generate images of internal organs of the human body.
Echocardiography: Echocardiography is a test that uses ultrasonic sound waves to produce live images of your heart.

9th Science Chapter 12 Study Of Sound Exercise Question 3.
To hear the echo distinctly, will the distance from the source of sound to the reflecting surface be same at all temperatures? Explain your answer.
Answer:

No,the distance from the source of sound to the reflecting surface will not be the same at all temperatures.
Velocity of sound is directly proportional to the square root of temperature.
One of the conditions of echo is that the time interval between the original and reflected sound should be more than 0.1 sec.
So if the temperature increases, the velocity of sound increases and the reflected sound reaches in less than 0.1 sec.
So for echo to be heard the distance between the observer and the reflecting surface has to increase.

9th Science Chapter 12 Study Of Sound Question 4.
When is the reflection of sound harmful?
Answer:

Reflected sound of high intensity called as noise is disturbing and harmful to the ears.
When sound reverberates i.e it undergoes multiple reflections, poor quality of sound is produced.

9th Class Science Chapter 12 Study Of Sound Question Answer Question 5.
What kind of waves are created when a stone is dropped in water ?
Answer:

When a stone is dropped in water, the particles of water oscillate up and down.
These oscillations are perpendicular to the direction of propagation of the wave, such waves are called transverse waves.

Answer the following question:

12 Study Of Sound 9th Class Question 1.
Observe the graph/ diagram and discuss your observation.
Answer:

Fig. A shows changes in density. The region where particles are crowded is called compression and where they are far apart are rarefaction.
Fig. B show change in pressure. The lines represent layers of air. The regions when lines are crowded are high pressure regions while when they are far apart are of low pressure.
Fig. C shows changes in density or pressure. The crest represents high pressure region while trough represents low pressure region.

Answer the following question:

Study Of Sound Class 9 Question Answer Question 1.
How are the frequencies of notes sa, re, ga, ma, pa, dha, ni related to each other?
Answer:
The frequencies of notes sa, re, ga, ma, pa, dha, ni are related in the ratio.

i.e if first Sa is 240Hz then the next Sa will be 240 x 2 = 480Hz

Class 9 Science Chapter 12 Study Of Sound Exercise Question 2.
What is the main difference between the frequencies of the voice of a man and that of a woman?
Answer:

Voice of a woman is high pitch i.e shorter wavelength and higher frequency
Voice of man is low pitch i.e larger wavelength and smaller frequency.

Question 3.
Try this;

(a) In the above activity, what will happen if you lift one of the tubes to some height?
Answer:
If one of the tubes is lifted, angle of incidence will not be equal to angle of reflection, hence, the sound will not be clearly audible.

(b) Measure the angle of incidence 01 and the angle of reflection 02. Try to see if they are related in any way.
Answer:
Angle of incidence is same as the angle of reflection.

Class 9 Science Chapter 12 Study of Sound Additional Important Questions and Answers

Can you recall?

12.Study Of Sound Question 1.
How is the direction of the oscillation of the particles of the medium related to the direction of propagation if the sound wave?
Answer:

Sound travels as a longitudinal wave.
In a longitudinal wave, the particle of the medium oscillate parallel to the direction of propagation of the wave.

Choose and write the correct option:

Class 9 Science Chapter 12 Study Of Sound Question 1.
The unit of frequency is ……………………………… .
(a) Hertz
(b) m/s²
(c) Decibels
(d) m/s
Answer:
(a) Hertz

Study Of Sound Class 9 Exercise Question 2.
The normal hearing range for humans is ……………………………… .
(a) 0 Hz to 20 Hz
(b) greater than 20,000 Hz
(c) 20 Hz to 20,000 Hz
(d) none of these
Answer:
(c) 20 Hz to 20,000 Hz

Class 9th Science Chapter 12 Study Of Sound Question Answer Question 3.
Sound will not travel through ……………………………… .
(a) Vacuum
(b) Liquid
(c) Solid
(d) Gases
Answer:
(a) vacuum

Class 9 Science Chapter 12 Study Of Sound Question Answer Question 4.
SI unit of ………………………………. is Hertz (Hz).
(a) Wavelength
(b) Frequency
(c) Speed of wave
(d) Velocity
Answer:
(b) frequency

Reflection Of Sound Class 9 Question 5.
The velocity of sound is inversely proportional to the ……………………………… .
(a) Pressure
(b) Square root of temperature
(c) Square root of density
(d) Humidity
Answer:
(c) square root of density

Question 6.
Sound waves with frequency greater than 20 kHz are called ……………………………… .
(a) Infrasound
(b) Ultrasound
(c) Sonic
(d) Damped sound
Answer:
(b) ultrasound

Question 7.
The loudness of a sound depends upon ……………………………… .
(a) Amplitude
(b) Speed
(c) Density
(d) Wavelength
Answer:
(a) Amplitude

Question 8.
……………………………… are used in sonography.
(a) High frequency ultrasound
(b) Stationary waves
(c) High frequency infrasound
(d) High frequency micro waves
Answer:
(a) High frequency ultrasound

Question 9.
The ……………………………… receives the vibrations coming from the membrane and converts them into electrical signals which are sent to the brain through the nerve.
(a) Cochlea
(b) Tympanic cavity
(c) Stapes
(d) Pinna
Answer:
(a) Cochlea

Find the odd one out:

Question 1.
Bats, rats, cats, dolphins
Answer:
Cats: cannot produce ultrasonic sound.

Question 2.
Clothes, paper, curtains, mirror
Answer:
Mirror: is a good reflector of sound, while others are poor reflectors.

Question 3.
Submarines, icebergs, internal organ, sunken ships.
Answer:
Internal organ: sonography is used , while for others sonar system is used.

Question 4.
Temperature, density, molecular weight, pressure
Answer:
Pressure: for a fixed temperature, the speed of sound does not depend on the pressure of the gas, all other factors affect speed of sound.

Answer in one sentence:

Question 1.
How can one produce sound?
Answer:
Vibration set up in an object produces sound (or) sound is produced when an object is disturbed and starts vibrating.

Question 2.
What is velocity of sound wave ?
Answer:
The distance covered by a point on the wave in unit time is the velocity of the sound wave.

Question 3.
What is the minimum distance of the reflecting surface to hear an echo ?
Answer:
To be able to hear a distinct echo, the reflecting surface should be at a minimum distance of 17.2 m.

Match the columns:

Question 1.

Column ‘A’	Column B’	Column C
(1) Transverse wave	(a) Particles oscillate parallel to direction of propagation	(i) Wave produced in a slinky
(2) Longitudinal wave	(b) Particles oscillate perpendicular to direction of propagation	(ii) Frequency less than 20 Hz
(3) Ultrasound	(c) Echo formation is heard under particular conditions	(iii) Wave produced in string
(4) Infrasound	(d) High frequency waves	(iv) Frequency between 20 Hz to 20000 Hz
(5) Audible frequency	(e) Low frequency waves	(v) Frequency greater than 20000 Hz

Answer:
(1-b- iii),
(2– a- i),
(3 – d – v),
(4 – e – ii),
(5 -c- iv)

Question 2.

Column A’	Column ‘B’	Column C
(1) Amplitude	(a) T	(i) Pitch of sound
(2) Frequency	(b) A	(ii) Loudness of sound
(3) Wavelength	(c) υ	(iii) Reciprocal of frequency
(4) Time period	(d) λ	(iv) v/υ

Answer:
(1 -b – ii),
(2 -c – i),
(3-d – iv),
(4 – a – iii)

Name the following:

Question 1.
A form of energy which produces sensation of hearing in our ears.
Answer:
Sound energy

Question 2.
Repetitions of sound due to reflection .
Answer:
Echo

Question 3.
The audible range of sound for human being.
Answer:
20 Hz to 20,000 Hz

Question 4.
A method to obtain images of internal organs of the human body.
Answer:
Sonography

Question 5.
The matter or substance through which sound gets transmitted.
Answer:
Solid, liquid, gases

Question 6.
Three major parts of the ear.
Answer:
External ear, the middle ear and the inner ear.

Question 7.
Any two examples in which infrasound is produced.
Answer:
Pendulum, earthquake.

Question 8.
Name the living beings that can produce ultrasound.
Answer:
Bats, dolphins, mice.

Give scientific reasons:

Question 1.
Bats can navigate in dark.
Answer:

The ultrasonic sound produced by bats, gets reflected on hitting an obstacle.
This reflected sound is received by their ears and they can locate the obstacle and estimate its distance even in the dark.
Hence, bats can navigate in dark.

Question 2.
A SONAR system is installed in a ship.
Answer:

A SONAR system determines the depth of the sea.
It locates underwater hills, valleys, icebergs, submarines and sunken ships. It also locates the positions of other ships or submarines.
Hence a SONAR system is installed in a ship.

Question 3.
Sound travels faster in iron than in air.
Answer:

Sound requires a material medium for its propagation and travels in the form of a longitudinal wave.
The denser the medium, faster is the propagation of sound.
Hence, sound travels faster in iron than in air.

Solve the following:

Type – A

Formula:
\(\text { (i) Velocity }=\frac{\text { distance }}{\text { time }}\)

Question 1.
Ultrasonic waves are transmitted downwards into the sea with the help of a SONAR. The reflected sound is received after 4 s. What is the depth of the sea at that place? (Velocity of sound in seawater = 1550 m/s)
Answer:
Given:
Time to hear echo = 4 sec
Time taken by sound waves to reach the bottom 4 of sea (t) = 4/2 sec = 2 sec
Velocity of sound in sea water (v) = 1550 m/s
To find:
Depth of sea(s) = ?

The depth of the sea at that place is 3100 m.

Question 2.
A person standing near a hill fires a gun and hears the echo after 1 second. If speed of sound in air is 340 m/s. Find the distance between the hill and the person.
Answer:
Given:
Time to hear echo = 1 sec 1
Time taken (t) = 1/2 sec
Velocity of sound (v) = 340 m/s
To find:
Distance (s) = ?

Distance between the person and hill is 170 m.

Numerical For Practice

Question 3.
If you hear the thunder 20 seconds after you see the flash of lightning, how far from you has the lightning occurred? (Speed of sound in air = 340 m/s)
Answer:
6800m

Question 4.
Aboy observes smoke from a cannon 3 seconds before he hears the bang. If the cannon is 1020 m from the observer, find the velocity of sound.
Answer:
340 rn/s

Question 5.
A soldier standing between the two buildings fires a gun. He heard the echo of the sounds from the first building after 2 seconds and echo from the second building after 3 seconds. Find the distance between two buildings. (Speed of sound in air = 340 m/s)
Answer:
850m

Type – B

\(Formula:
(i) Velocity = Frequency \times Wavelength
(ii) Velocity =\frac{\text { distance }}{\text { time }}\)

Question 1.
Sound waves of wavelength 1 cm have a velocity of 340 mIs in air. What is their frequency? Can this sound be heard by the human ear?
Answer:
Given:
wave length (λ) = 1cm = 1/100
Velocity of sound (v) = 340 m/s
To fInd :
frequency (u) = ?
Formulae:
ν = υ λ
Solution:

The frequency of the sound waves is 34000 Hz. The frequency is higher than 20000 Hz and therefore, this sound cannot be heard by the human ear.

Question 2.
How long will it take for a sound wave of 25 cm wavelength and 1.5 kHz frequency, to travel a distance of 1.5 km?
Answer:
Given:
frequency (u) = 1.5 kHz = 1500 Hz

\(\begin{array}{l}
=\frac{1500}{375} \\
=4 \mathrm{sec}
\end{array}\)
The sound wave takes 4 sec to travel the distance of 1.5 km.

Question 3.
Calculate distance travelled by a sound wave having frequency 1000 Hz and wavelength 0.25 m, if it travels for 5 seconds in a certain medium.
Answer:
Given:
frequency (u) = 1000 Hz
wavelength (λ) = 0.25 m
time (t) = 5 seconds
To find :
Distance (d) =?
Formulae:
ν = υ λ
Solution:

The distance travelled by the sound wave is 1250 m.

Question 4.
The audible range of sound is 20 Hz to 20000 Hz. At 22°C in air speed of sound is 344 mIs. Express the range of sound in terms of wavelength by calculating the respective values.
Answer:
Given:
frequency (u₁) 20 Hz
frequency ( u₂) = 20,000 Hz
velocity (v) = 344 rn/s
To find :
Wavelengths λ₁ and λ₂= ?
Formulae:
ν = υ λ
Solution:

Audible range of wavelength of sound is from 17.2 x 10^-3 m to 17.2 m.

Numerical For Practice

Question 5.
A sound wave has frequency 320 Hz and wavelength 0.25 m. How much distance will it travel in 10 second?
Answer:
The distance travelled is 800 m.

Type – C

Question 1.
Hydrogen gas is filled in two identical bottles, A and B, at the same temperature. The mass of hydrogen in the two bottles is 12 gm and 48 gin respectively. In which bottle will sound travel faster? How many timés as fast as the other?
Answer:
Given:
Mass of hydrogen in bottle A (m_A) = 12gm
Mass of hydrogen in bottle B(m_B) = 48gm
To find:
In which bottle sound travels faster.
Formulae:

Since both bottles are identical hence, the volume is the same, i.e. v
Dividing (j) and (ii),

(i) Vivacity of sound will be more in bottle A.
(ii) Velocity of sound in bottle A (V_A) is twice of that in bottle B (v_B)

Numerical For Practice

Question 2.
Argon gas is filled in two identical bottles X and Y. The mass of the gas in the two bottles is 5 gm and 25gm respectively. If the speed of sound is the same in both bottles, what conclusions will you draw?
Answer:
(Temperature of Y is 5 times the temperature of X.)

Type – D

Numerical For Practice

Question 1.
Velocity of sound in air at 0°C is 332nVs. It increases by 0.6ni/s for each °Celsius rise in temperature. At what temperature of ait the velocity will be 359m1s?
Answer:
45°C

Question 2.
Velocity of sound In air at 0°C is 332m/s It increases by 0.6mIs for each degree Celsius rise In temperature. What will be the velocity of sound at 60°C?
Answer:
368 rn/s

Define the following:

Question 1.
Wave length (λ)
Answer:
The distance between two consecutive compressions (or crests) or two consecutive rarefactions (or troughs) is called the wavelength.

Question 2.
Amplitude (A)
Answer:
The maximum value of pressure or density is called amplitude.

Question 3.
Frequency (υ)
Answer:
The frequency of a sound wave is defined as the number of complete oscillations of density (or pressure of the medium) per second.

Question 4.
Time Period (T)
Answer:
The time taken for one complete oscillation of pressure or density at a point in the medium is called the time period.

Question 5.
Echo
Answer:
An echo is the repetition of the original sound because of reflection by some surface.

Question 6.
Transverse waves
Answer:
Oscillations of the particles of the medium vibrate at right angles to the direction of propagation of the wave are called transverse waves.

Question 7.
longitudinal waves
Answer:
The particles of the medium oscillate about their central or mean position in a direction parallel to the propagation of wave is called as longitudinal waves.

Question 8.
Velocity of wave
Answer:
The distance covered by a point on the wave (for example the point of highest density or lowest density) in unit time is the velocity of the sound wave.’

Distinguish between:

Question 1.
Infrasound and Ultrasound
Answer:

	Infrasound		Ultrasound
(i)	Longitudinal waves whose are below 20 Hz are called Infrasound waves. frequencies Infrasonic or	(i)	Longitudinal waves whose frequencies lie- above 20,000 Hz are called Ultrasonic or ultrasound waves.
(ii)	Whales, elephants produce sound in the infrasound range.	(ii)	Bats produce (30 kHz to 50 kHz) frequency and dolphins produce ultrasound (100 kHz).

Question 2.
Transverse waves and Longitudinal waves
Answer:

Transverse waves	Longitudinal waves
(i) Particles of the medium vibrate at right angles to the direction of propagation of the wave. (ii) They produce crests and troughs. (iii) For transverse waves, a wavelength is made up of one crest and one trough.	(i) Particles of the medium vibrate parallel to the direction of propagation of the wave. (ii) They produce compression and rarefaction. (iii) For longitudinal waves, a wavelength is made up of one compression and one rarefaction.

Question 3.
Consider two cases
(A) whistle of train (B) roar of a lion

(I) In which case the sound is high pitch?
Answer:
Whistle of a train is high pitch as compared to roar of a lion, as the frequency is higher.

(II) What is the real cause of sound production? Explain with examples.
Answer:

Vibrations in the object are responsible to produce a sound.
Vibration is a rapid to and fro motion of an object.
Sometimes the vibrations may be strong enough to be seen by eyes, e.g. string vibrations in string instruments, vibration on mobile phone, blowing air in the cap of your pen by holding it near the lips.

(III) Three sounds 5 Hz, 500 Hz and 50,000 Hz are produced by different sources.
(a) Which sound will be heard by humans?
(b) Which sounds may be produced by bats?
(c) Which sounds may be produced by elephants?
Answer:
(a) 500 Hz – Humans can hear sounds in the range of 20 Hz-20,000 Hz
(b) 50,000 Hz – Bats produce ultrasonic sounds above 20,000 Hz
(c) 5 Hz – Elephants can produce infrasonic sounds below 20 Hz

Question 6.
Suppose you and your friend are on the moon. Will you be able to hear any sound
Answer:
Sound waves need a material medium for their propagation. Since there is no atmosphere on the moon, we cannot hear any sound on the moon.

Answer in detail:

Question 1.
What are the factors on which velocity of sound in gaseous medium depend?
Answer:
The velocity of sound in a gaseous medium depends on the physical conditions i.e. the temperature, density of the gas and its molecular weight.

Temperature (T): The velocity of sound is directly proportional to the square root of the temperature of the medium. This means that increasing the temperature four times doubles the velocity.
\(\text { v } \alpha \sqrt{\mathrm{T}}\)
Density(p): The velocity of sound is inversely proportional to the square root of density. Thus, increasing the density four times, reduces the velocity to half its value.
\(\mathrm{v} \alpha \frac{1}{\sqrt{\rho}}\)
Molecular weight (M): The velocity sound is inversely proportional to the square root of molecular weight of the gas. Thus, increasing the molecular weight four times, reduces the velocity to haff its value.
\(\mathrm{v} \alpha \frac{1}{\sqrt{\mathrm{M}}}\)

Question 2.
What are the uses of ultrasonic sound?
Answer:
Uses of ultrasonic sound are as follows:

For communication between ships at sea.
To join plastic surfaces together.
To sterilize liquids like milk by killing the bacteria in it so that the milk keeps for a longer duration.
Echocardiography which studies heartbeats, is based on ultrasonic waves (Sonography technology).
To obtain images of internal organs in a human body.
In industry to clean intricate parts of machines where hands cannot reach.
To locate the cracks and faults in metal blocks.

Question 3.
Explain with the help of a neat labelled diagram the working of human ear.
Answer:

The ear is an important organ of the human body.
When sound waves fall on the eardrum, it vibrates and these vibrations are converted into electrical signals which travel to the brain through nerves.
The ear can be divided into three parts:
(a) Outer ear
(b) Middle ear
(c) Inner ear.

(a) Outer ear or Pinna
The outer ear collects the sound waves and passes them through a tube to a cavity in the middle ear. Its peculiar funnel like shape helps to collect and pass sounds into the middle ear.

(b) Middle ear
There’ is a thin membrane in the cavity of the middle ear called the eardrum. When a compression in a sound wave reaches the eardrum, the pressure outside it increases and it gets pushed inwards. The opposite happens when a rarefaction reaches there. The pressure outside decreases and the membrane gets pulled outwards. Thus, sound waves cause vibrations of the membrane.

(c) Inner ear
The auditory nerve connects the inner ear to the brain. The inner ear has a structure resembling the shell of a snail. It is called the cochlea. The cochlea receives the vibrations coming from the membrane and converts them into electrical signals which are sent to the brain through the nerve. The brain analyses these signals.

Question 4.
Write a short note on SONAR
Answer:

(i) SONAR is the short form for Sound Navigation and Ranging. It is used to determine the direction, distance and speed of an underwater object with the help of ultrasonic sound waves. SONAR has a transmitter and a receiver, which are fitted on ships or boats.

(ii) The transmitter produces and transmits ultrasonic sound waves. These waves travel through water, strike underwater objects and get reflected by them. The reflected waves are received by the receiver on the ship.

(iii) The receiver converts the ultrasonic sound into electrical signals and these signals are properly interpreted. The time difference between transmission and reception is noted. This time and the velocity of sound in water give the distance from the ship, of the object which reflects the waves.

(iv) SONAR is used to determine the depth of the sea. SONAR is also used to search underwater hills, valleys, submarines, icebergs, sunken ships etc.

Question 5.
Write a short note on Sonography. How is it misused?
Answer:

Sonography technology uses ultrasonic sound waves to generate images of internal organs of the human body.
This is useful in finding out the cause of swelling, infection, pain, condition of the heart, the state of the heart after a heart attack as well as the growth of foetus inside the womb of a pregnant woman.
This technique makes use of a probe and a gel.
The gel is used to make proper contact between the skin and the probe so that the full capacity of the ultrasound can be utilized.
High-frequency ultrasound is transmitted inside the body with the help of the probe.
The sound reflected from the internal organ is again collected by the probe and fed to a computer which generates the images of the internal organ.
As this method is painless, it is increasingly used in medical practice for correct diagnosis.
This technique is used by many people to find out gender of an unborn baby and this often leads to the incidence of female foeticide.

9th Std Science Questions And Answers:

Std 9 Geography Chapter 11 Question Answer Maharashtra Board

February 4, 2025January 3, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Geography Solutions Chapter 11 Transport and Communication Notes, Textbook Exercise Important Questions and Answers.

Transport and Communication Class 9 Questions And Answers Maharashtra Board

Class 9 Geography Chapter 11 Transport and Communication Questions And Answers Maharashtra Board

Geography Class 9 Chapter 11 Question Answer Maharashtra Board

1. Differentiate between:

(A) Railways and roadways
Answer:

Basis	Railways	Roadways
(1) Carrying Capacity	Carrying capacity is more	Carrying capacity is limited
(2) Distance	Suitable for long distances	Suitable for short distance
(3) Door to door service	Railway does not provide door to door service.	Roadways provide door to door service.
(4) Traffic	There is no problem of traffic jam on railways.	There is a problem of traffic jam on roadways.
(5) Pollution	Railways do not create a problem of air pollution.	Roadways create a problem of air pollution.

(B) Transportation and communication
Answer:

Basis	Transportation	Communication
(1) Meaning	Transportation is the movement of humans, animals and goods from one location to another.	Communication is the exchange of information, ideas and messages by speaking, writing or some other medium.
(2) Means	It is done through railways, roadways, waterways, airways and pipelines.	It is done through telephones, mobiles, video-conferencing, email and post etc.
(3) Threats	The threats like a traffic jams, accidents, noise pollution, air pollution are associated with transportation.	The threats like technical issues, cyber crimes, etc. are associated with the communication.

Basis	Conventional means of Communication	Modem means of Communication
(1) Meaning	The means of communication – used since olden times – conventional means of communication.	The means of communication – used in modern times – modern means of communication.
(2) Examples	Letter, newspapers, radio, television.	Mobile phone, internet, etc.
(3) Interaction	May not facilitate the direct interaction between – sender and receivers of information.	Facilitates the direct interaction between – sender and the receivers of information.

2. Answer in detail:

Question 1.
‘Newspapers are used for communication’. Explain the statement.
Answer:

The news related to economic events, politics, social issues, culture, education, etc. are published in newspapers.
Newspapers arecheap means of communication. Through newspapers information gets spread to masses at a time.
Newspapers are published in various languages.
In this way, newspapers are used for communication.

Thus, newspapers are used for communication.

Question 2.
Explain how T.V. is a cheap means of communication.
Answer:

Various programs, serials, etc. related to entertainment, social issues, culture, education, politics, economic events, sports, weather conditions, etc. are broadcasted on television.
Through television the information is exchanged to masses at a time with high speed.
Television can broadcast both audio and video for communication. In this way, television is a cheap means of communication.

Thus, TV is a cheap means of communication.

Question 3.
What types of communications can be done through mobiles?
Answer:

Calling and SMS (Short message system) facilitates easy one-to-one communication, using mobiles anywhere and at any time.
Video conferencing and applications like ‘Whatsapp’ allow one to communicate with many people simultaneously.
Various functions like, money transfer, payment of bills, purchase of goods and services and online trading can be done using smart phones’ various apps like BHIM, SBI anywhere, etc.
Internet and social media can also be accessed through mobile phones.

3. Name them on the basis of the given information:

Question 1.
Five cities with airways services in Maharashtra
Answer:
Mumbai, Pune, Nagpur, Kolhapur, Aurangabad, Nashik and Nanded.

Question 2.
Services available in post offices
Answer:

Financial Services: Saving schemes, insurance services and mutual fund.
Mail services: Speed post, postcard, parcel and courier.

Question 3.
National Highways near your area
Answer:

Mumbai- Goa Highway (NH 66)
Mumbai- Bangaluru highway (NH 04)
Mumbai- Agra Highway (NH 08)
Note: Answer may vary.

Question 4.
Ports along the coast of Maharashtra
Answer:

Malvan
Venture
Vasai
Dahanu
Gharapuri

4. Identify the relation and match the columns making a chain

Group ‘A’	Group ‘B’	Group ‘C’
(1) Postal services	Roadways	Speed post
(2) Shivneri	World network of connected computers	Exchange of information
(3) Internet	Conventional means of communication	Comfortable journey
(4) RoRo transport	Railways	Energy, time and labour saving

Answer:

Group ‘A’	Group ‘B’	Group ‘C’
(1) Postal services	Conventional means of communication	Speed post.
(2) Shivneri	Roadways	Comfortable journey.
(3) Internet	World network of connected computers	Exchange of information.
(4) RoRo transport	Railways	Energy, time and labour saving.

5. Read the following maps and answer the questions:
Maharashtra Board Class 9 Geography Solutions Chapter 11 Transport and Communication 1

Question 1.
In which region do you find a dense network of transport routes in the map?
Answer:
The central part of the district has dense network of transport routes.

Question 2.
How is the physiography of the region with dense network?
Answer:
The central part of the district has lower and medium elevation as compared to the Western part.

Question 3.
Which region has a sparse network of transport routes?
Answer:
The transport network is sparse in the Eastern part of the district.

Question 4.
How is the physiography of this region?
Answer:
The region with sparse network of transport . routes is comparatively of lower and medium elevations.

Question 5.
Look for the region lacking transport routes.
Answer:
The Western region lacks transport routes.

Question 6.
What kind of obstruction can you find there?
Answer:
Sahyadri Mountains and Shivsagar reservoir of Koyna dam are the obstructions found here.

Class 9 Geography Chapter 11 Transport and Communication Intext Questions and Answers

Let’s Recall

Complete the following table:

Transport	Means of	Used for
Route	Transport
Roadways	Rickshaw	Passengers
Roadways	Trucks
	Metro
Waterways
	Helicopter
Airways
	Submarine
Waterways		Freight
	Mules
Railways
Pipelines

Answer:

Transport	Means of Transport	Used for
Roadways	Rickshaw	Passengers
Roadways	Trucks	Goods
Railways	Metro	Passengers
Waterways	Cruise/Boats	Passengers
Airways	Helicopter	Passengers
Airways	Aeroplane	Passengers
Waterways	Submarine	Defence & Research
Waterways	Cargo-ship	Freight / Goods
Roadways	Mules	Goods
Railways	Cargo goods train	Goods
Pipelines	Pipes	Oil, Water and Gas

Can you tell?

We have given some specific conditions. In this context, tell with reasons which means of transport route will you take?

Question 1.
You have to reach Bhopal from Nagpur due to some emergency.
Answer:
Airways : As it is the fastest mode of transport.

Question 2.
You have to reach Kanyakumari carrying the message of cleanliness. There is no time limit for it.
Answer:
Roadways : Since roadways connect even the remotest places the message can reach to all persons.

Question 3.
Send the Alphonso mangoes from Konkan to Arab countries.
Answer:
Airways – Since mango is a perishable commodity, the fastest mode of transportation is used. ,

Question 4.
Indrayani variety of rice has to be exported from Pune to Cape Town of South Africa at low expenditure.
Answer:
In such conditions, we will choose waterways as a route and ship as a means of transport. Because rice is comparatively durable agricultural good in the given situation it has to be transported at low cost.

Question 5.
Large-scale production of vegetables in Nandurbar has taken place but is not fetching a good price. The Nagpur-Surat National Highway and the Surat-Bhusawal Railway line passes through the district.
Answer:
In a given situation, we will choose roadways and railways as a route and truck and goods’ ways/train respectively as a means of transport. Because the highway and railway line that pass through the district, connects the important towns and cities from the district.

Question 6.
You have to go to Singapore from your village/ town. You have 10 days to do the same.
Answer:
Roadway and Airways: I will first reach the nearest airport of a city by road and then take an Airway. It is the fastest mode of transport.

Can you tell?

Question 1.
Make a list of various means of communication you are aware of.
Answer:
Letters, radio, television, telephones, mobile phones, newspaper, internet, satellites etc. are the various means of communication.

Question 2.
How many of these do you actually use? Make a box around them.
Answer:
Maharashtra Board Class 9 Geography Solutions Chapter 11 Transport and Communication 2

Question 3.
For what do you use them ?
Answer:
We use these means of communication to exchange important information, ideas, opinions etc. with friends, parents, relatives and teachers.

Question 4.
Who uses the remaining means ?
Answer:
The remaining means are used by parents, other relatives, businessmen from locality and government agencies.

Can you do it?

Observe the image and the instructions given on page 87 of the textbook and answer the following questions:

Question 1.
Which are the dates mentioned in the image?
Answer:
The dates mentioned are 15/5/2017 and 19/5/2017

Question 2.
What does the information in the image tell?
Answer:
The image informs that the person’s email account has been hacked. He cannot access his important files as they have been encrypted and to recover his files, he will have to pay a certain amount to the hacker.

Question 3.
What is the price asked for recovering the files and in what currency?
Answer:
The price asked for recovering the files is 300 US dollars in bitcoins.

Question 4.
What is the type of crime here?
Answer:
This is a cyber crime.

Give it a try
Think about the transport issues you come across during your journeys. Write the innovative changes you would suggest in the transport routes or means in your copy.

Question 1.
Congested city roads and Pollution
Answer:
Electric cars which are smaller and smarter.

Question 2.
Time-consuming travel
Answer:
Dedicated bus corridors, carpooling, more number of Expressways.

Give it a try

Question 1.
Look for the other uses of artificial satellites? Try to understand how they are related to your daily life?
Answer:
(a) The other uses of artificial satellites are as follows:

Studying about other planets.
Live broadcasting of a program/event from any region of the earth.
Studying the resources on the earth’s surface.
Regional planning.
Planning defense strategies.
Forecasting weather etc.

(b) The artificial satellites are directly or indirectly related to personal, social, educational, economic, cultural, political aspects in everyone’s daily life. For eg. through artificial satellites, one can enjoy a live program like award functions/cricket match, etc. on television.

Class 9 Geography Chapter 11 Transport and Communication Additional Important Questions and Answers

Complete the statement choosing the correct option from the bracket:

Question 1.
The price of the goods can be kept low if the transportation is ………….. .
(a) feasible
(b) expensive
(c) costly
(d) affordable
Answer:
(d) affordable

Question 2.
…………… growth gets a boost due to transportation.
(a) Physical
(b) Culture
(c) Economic
(d) Political
Answer:
(c) Economic

Question 3.
Freight transport through …………… is costlier than railways.
(a) trucks
(b) horses
(c) bullock-cart
(d) yak
Answer:
(a) trucks

Question 4.
The western part of Satara district is occupied by the …………… of its off shoots.
(a) Vindhyas
(b) Satpudas
(c) Sahyadris
(d) Aravallis
Answer:
(c) Sahyadris

Question 5.
The use of RORO (Roll on Roll off) services started in …………… railways in India.
(a) Goa
(b) Maharashtra
(c) Konkan
(d) Pune
Answer:
(c) Konkan

Question 6.
In the modem age, man-made …………… are an important and effective means of communication.
(a) planets
(b) asteroids
(c) satellites
(d) rockets
Answer:
(c) satellites

Question 7.
Satellite images obtained by …………… facilitate study of resources on Earth’s surface and help in regional planning.
(a) GPS
(b) radio
(c) remote sensing1
(d) drones
Answer:
(c) remote sensing

Question 8.
Communication is not just limited to talking on telephones or sending messages but …………… is also available now.
(a) tele-calling
(b) STD-Calling
(c) video-calling
(d) Local-calling
Answer:
(c) Video-calling

Question 9.
There is a correlation between transport routes and the …………… of region.
(a) soil type
(b) rainfall
(c) climate
(d) physiography2
Answer:
(d) physiography

Question 10.
Transport facilities can develop well in …………… region.
(a) mountainous
(b) plain
(c) forest
(d) plateau
Answer:
(b) plain

Question 11.
Shiv sagar reservoir of the …………… dam is located in the Satara district.
(a) Ram Krishna
(b) Bhakra-Nagal
(c) Koyna
(d) Tehri
Answer:
(c) Koyna

Question 12.
The …………… part of Satara district has a dense transport network.
(a) Western
(b) Central
(c) Eastern
(d) Southern
Answer:
(b) central.

Write answers in one sentence

Question 1.
What is transportation?
Answer:
The movement of goods and people from one place to another is called transportation.

Question 2.
Which are the different kinds of transport routes?
Answer:
Roadways, railways, waterways, airways and pipelines are the different kinds of transport routes.*

Question 3.
For what reasons does a region become devoid of any transport route?
Answer:
Due to mountains, valleys, rivers, reservoirs

remote sensing – obtaining information regarding any place or an object without actually establishing direct contact with it is called remote sensing.
physiography – nature and slope of land and undulating1 topography2 a region becomes devoid of any transport route.

Question 4.
Why does a dense network of transportation develop in some regions?
Answer:
A dense network of transportation develops in some regions due to lower and medium elevation, plains, flat and regular topography, etc.

Question 5.
What does Ro-Ro transport stand for?
Answer:
Ro-Ro transport is Roll-on, Roll-off transport.

Question 6.
Why was the Ro-Ro transport introduced?
Answer:
Freight transport by trucks is costlier than railways, so as a solution the Ro-Ro transport has been introduced.

Question 7.
What are Cyber Crimes?
Answer:
Crimes like website/email hacking, theft of information, economic frauds, wars, terrorism, etc. that are committed by using computers and internet are called ‘cyber crimes’.

Question 8.
How are BHIM app, SBI anywhere app useful?
Answer:
BHIM App, SBI Anywhere app, helps us to pay various bills, sell, buy and carry out various transactions through mobile phones.

Question 9.
Where was Ro-Ro service introduced for the first time in India?
Answer:
Ro-Ro service, was introduced for the first time in India by the Konkan Railway.

Give Reasons:

Question 1.
The development of transportation is an indicator of the development of that region.
Answer:

With development of transportation there is an increase in the movement of freight and passengers of that region.
Development of transportation develops industries and markets.
Per capita Income (PCI) and Gross Domestic product (GDP) increases leading to economic growth.
So it is said that development of transportation is an indicator of the development of that region.

Question 2.
Green Corridor saves many lives.
Answer:

Green Corridor is a route cleared of all traffic obstacles, so that a dead person’s (donor’s) organs can be speedily transported to the receiver
It is called ‘green’ corridor because the traffic lights are turned green for the speedy movement of the vehicle carrying the organ.
Thus, Green Corridor saves many lives.

Question 3.
Ro-Ro Transport helps to reduce cost of transport.
Answer:

In Ro-Ro (Roll-on, Roll-off) transport, the trucks loaded with goods are transported to desired railway stations through a goods train.
From there the trucks take the goods ahead to the desired locations.
Ro-Ro transport helps to reduce the cost of transport as railways are used for the part of the distance.
Ro-Ro transport also reduces cost of fuel and pollution caused by trucks.

Answer in details:

Question 1.
Give the Importance of transportation.
Answer:
Transportation is a basic infrastructure.
The development of transportation infrastructure is an indicator of the development of the particular region or a country.

The importance of transportation can be explained with the help of the following points :

Extending trade and network.
Rapid industrialisation.
Availability of employment opportunities.
Regional connectivity.
Utility of the site.
Overcoming scarcity (deficit).
Decreasing regional imbalance1.
Tourism development.

Question 2.
Give the Importance of a communication system.
Answer:

Communication or exchange of information is an important process in today’s era. Communication is basic infrastructure.
Man-made satellites are an important and effective means of communication.
The exchange of messages through mobiles, watching progammes on television, getting updates of climatic condition etc. is possible simultaneously through man-made satellites.
Satellite images obtained by remote sensing facilitate study of resources on earth’s surface and helps in regional planning.
Many apps which can be used on mobile phones have been developed for the same.
For e.g. BHIM app, SBI anywhere, etc. By using these communicational facilities, we can pay various bills, sell and buy goods and services and carry other such transactions.
Nowadays, communication is not just limited to talking on telephone or sending messages but also video calling is available now.

Explain:

Question 1.
Factors to be kept in mind while selecting the route way and the means of transport.
Answer:
The following factors should be kept in mind while selecting the route way and means of transport:

Distance
Duration
Cost
Time
Products
Climate
Market
Routes and means
Physiography

Question 2.
Importance of Transportation.
Answer:

The development of transportation infrastructure is an indicator of the development of the country or that region.
The reforms in the transport sector enhance the dynamicity of freight and passengers in a region.
Industries and markets develop. Economic growth gets a boost. Per Capita Income (PCI) and Gross Domestic Product (GDP) increases too.
Transportation leads to –
- Extending trade and network
- Rapid industrialisation
- Availability of employment opportunities
- Regional connectivity
- Utility of the site
- Overcoming scarcity (weakness)
- The decrease in regional imbalance
- Tourism development

Question 3.
Importance of man-made satellites.
Answer:

In the modern age, man-made satellites are an important and effective means of communication.
The exchange of messages through mobiles, watching programmes on TV and getting updated information regarding climatic conditions is possible simultaneously through man-made satellites.
Satellite images obtained by remote sensing facilitate study of resources on earth’s surface and help in regional planning.

Thus, man-made satellites are important.

Question 4.
Green Corridor.
Answer:

It happens that sometimes a dead person has donated his organs.
In such cases, such organs need to be transported from the donor’s location to the receiver urgently.
For this organ transfer, all types of routes are cleared of all obstacles. This is called Green Corridor.
Consequently, this kind of rapid transport corridor can save the receiver’s life.

Question 5.
Threats associated with means of communication.
Answer:

Besides facilities, means of communication have a few threats associated with them.
Many crimes are happening through the internet like website/email hacking, fraud, theft, attack, wars and terrorism. Possibilities of threats like theft of information, economic frauds, attacking important websites etc. arise.
Therefore, one should take precautions while using social networks.
One should not reveal personal information before ensuring safety.
One should not put any sensitive information or personal information on social networking sites, blogs, etc.

9th Std Geography Questions And Answers:

Std 9 Geography Chapter 9 Question Answer Maharashtra Board

February 4, 2025January 3, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Geography Solutions Chapter 9 Trade Notes, Textbook Exercise Important Questions and Answers.

Trade Class 9 Questions And Answers Maharashtra Board

Class 9 Geography Chapter 9 Trade Questions And Answers Maharashtra Board

Geography Class 9 Chapter 9 Question Answer Maharashtra Board

1. Classify the trade taking place between the following regions:

(1) Maharashtra and Punjab
(2) India and Japan
(3) Lasalgaon and Pune
(4) China and Canada
(5) India and European Union
Answer:
(1) Internal trade
(2) International trade
(3) Internal trade
(4) International trade
(5) International trade

2. Write the correct word- Import or Export for the following :

(1) India buys crude oil from the Middle-East Asian countries.
(2) Wheat is sent to Asian countries from Canada.
(3) Japan sends machine parts to APEC countries.
Answer:
(1) Import
(2) Export
(3) Export

3. Correct and rewrite the wrong statements:

(A) India is a self-sufficient country.
Answer:
India is not a self-sufficient country as it depends on other countries for crude oil, machinery, etc.

(B) The place where there is excess production does not have demand for those products.
Answer:
The place where there is excess production more creates ‘supply’ for those products.

(C) International trade processes are easier than local trade.
Answer:
International trade processes are relatively more difficult than local trade.

4. Identify and write the type of trade:

(A) Srushti brought sugar from the grocery shop.
Answer:
Retail Trade.

(B) The traders from Surat bought cotton from the farmers of Maharashtra.
Answer:
Wholesale Trade.

(D) Sadabhau bought 10 sacks of wheat and 5 sacks of rice from Market Yard for selling in his own shop.
Answer:
Wholesale Trade.

5. Write answers in short:

(A) Create a flowchart showing the types of trade
Answer:
Trade refers to buying and selling for fulfilling each other’s needs.
Trade is divided into two categories:

On the basis of the quantity of goods.
On the basis of the extent of trade region.

(B) Explain the difference in types of balances of trade.
Answer:
The difference between the import and export values of a country in a specific period is called balance of trade.
The different types of balance of trade are:

Unfavourable Balance of Trade: When the value of imports is more than the value of exports, it is called ‘Unfavourable Balance of Trade.’
Favourable Balance of Trade: When the value of exports is more than the value of imports, it is called ‘Favourable Balance of Trade.’
Balanced Balance of Trade: When the value of exports and imports is almost the same, it is called ‘Balanced Balance of Trade.’

To provide platform for negotiations in international trade.
To handle the differences related to trade.
To monitor the trade policies of member states.
To provide a technological assistance and training to developing countries.

(D) What is the difference between the OPEC and APEC in terms of their functions?
Answer:

OPEC	APEC
(i) OPEC stands for Organisation of Petroleum Exporting Countries.	APEC stands for Asia-Pacific Economic Cooperation (APEC).
(ii) OPEC is the organisation of oil-producing and exporting countries.	APEC is the regional organisation of the countries in the Asia Pacific region.
(iii) It keeps control over the international trade of crude oil.	It promotes free trade and economic cooperation among the member countries.
(iv) It keeps control on the rates of crude oil production among member states.	It promotes regional and technical cooperation among members.

(E) Write the functions of the important trade organisations in Asia.
Answer:
Important trade organisations in Asia are:
Association of South East Asian Nations (ASEAN)

To expand social and cultural harmony along with economic growth in South East Asia.
To promote regional peace.
To promote tax waivers for trade growth in member states.

Asia Pacific Economic Co-operation (APEC)

To promote free trade and economic co¬operation in the Asia-Pacific Ocean region.
To promote regional and technical co-operation among members.

(F) What is the importance of marketing from farmers ‘point of view’?
Answer:
Marketing involves price of a commodity, its sales promotion, its advertising and its proper distribution.

In the traditional marketing system, the farmers used to sell their products in the local market at whatever price available. This is because the fruits and vegetables are perishable, so the farmers used to incur losses,
However, the modem farmers have acquired skills in marketing. They are aware of the trends in the market.
They produce food grains and fruits as per the international standards.
They undertake grading and packaging of their products. The presentation of any product has become indispensable now.
They advertise the quality of their product and keep the same for sale, along with samples, in the mall.
These commercial-minded farmers contact the supermarkets and exporters through the internet.
As a result, their products are sold at a higher price in the malls. They also fetch a good price from exports.
Thus marketing is as important as the cultivation of crops. By following modem marketing techniques, the income of the farmers can increase and that can improve their standard of living.

6. In the following table, export-import of some countries in the year 2014-15 is given in million U.S. dollars. Make a compound bar graph of the given statistical information. Read the bar diagram carefully and comment upon the balance of payments of the respective countries.

Country	Export	Import
China	2143	1960
India	272	380
Brazil	190	241
USA	1510	2380

Answer:
Maharashtra Board Class 9 Geography Solutions Chapter 9 Trade 1

China has a balance of trade.
India, USA and Brazil have an unfavourable balance of trade.
The volume of international trade of China and the USA is maximum.
International trade of India and Brazil is insignificant.
International trade is dominated by China and the USA.

Class 9 Geography Chapter 9 Trade Intext Questions and Answers

Make friends with maps!

Find out the names of the member-states of the following organisation with the help of internet. Show these member nations on the outline map given in the figure using different colour for each organisation.
(1) OPEC member – countries
(2) SAARC member – countries
Answer:
Maharashtra Board Class 9 Geography Solutions Chapter 9 Trade 2

(1) OPEC member- countries
Republic of Iran, Iraq, Kuwait, Saudi Arabia, Venezuela, Qatar, Libya, The United Arab Emirates, Algeria, Nigeria, Ecuador, Gabon, Angola, Equatorial Guinea (2017).

(2) SAARC countries
Afghanistan, Bangladesh, Bhutan, India, Nepal, Maldives, Pakistan, Sri Lanka.

Can you tell?

With a lot of hard work Dhondiba used to grow best varieties of vegetables and other agricultural commodities. But his products could not fetch a good price. His college-going son, saw this situation and he first packed the commodities nicely after cleaning them neatly. Then he contacted the supermarket in the town. Looking at the quality of his product, they advertised the farm product and kept it for sale in the mall. Today, Dhondiba’s commodities are being sold for higher prices than before.

Question 1.
Why did Dhondiba’s commodities start getting higher prices?
Answer:
For any commodity to be accepted in the market and fetch a better price, it should have an appropriate presentation. The price of the commodity is determined by its quality, its grading and how it is presented before the customer. Dhondiba’s son who was educated, realized this and took the necessary actions in time which helped Dhondiba to fetch better price.

Question 2.
What did Dhondiba’s son do for that?
Answer:
Dhondiba’s college-going son realised that the agricultural commodities sold by his father lacked proper presentation and marketing. So he adopted modem marketing practices like cleaned the commodities well and packed them nicely. He then got in touch with the supermarket in the town. The supermarket was impressed with the quality of Dhondiba’s products, they advertised the farm product and kept it for sale in the mall. Dhondiba’s commodities were in great demand and sold at higher prices than before.

Question 3.
What measures would you suggest to the farmers near you so that then commodities can fetch a good price?
Answer:
Some of the measures that we can suggest to the farmers so that then commodities can fetch a better price are:

Clean their vegetables, fruits well.
Grade the commodities.
Pack them nicely.
Advertise their farm products.
Sell it in the market.

Give it a try.

Obtain information regarding the bilateral trade between India and Japan for any financial year and the value of the export and import of major goods. Write two paragraphs on it.
Answer:
India’s Trade with Japan (April 2016-Jan 2017)

Exports	₹ 20,000 Cr
Imports	₹ 55,000 Cr
Trade Balance	₹ 35,000 Cr

This shows that India has an Unfavourable Balance of Trade with Japan, in which the value of Imports is more than the value of Exports.

India’s major exports to Japan
Petroleum products, Iron ore, Fish Meat (including lobsters, crabs, shrimps etc) Motor parts, Insecticides, Fungicides, Turbo-jets, Gas turbines etc.

India’s major imports from Japan
Iron and Steel Products, Transport Equipments, Plastic, Machinery items like Drilling Platforms, Floating Cranes, Printing machinery etc.

Think about it.

Question 1.
What will happen if there is only one currency used in the whole world?
Answer:
The European Union is an example, which has one common currency ‘Euro’.
Advantages of having one common currency. If the whole world has one common currency, international trade will become much easier and move will increase international trade also. Disadvantages of having one common currency.

If all the countries adopt one common currency, there will be one uniform policy. No country will be able to have their own monetary and fiscal policy.

Find out.

You get products from other places. Similarly, find out where the special products/items made in your village/city are sent?
Answer:
I live in Mumbai.
Special products exported from Mumbai and where they are sent:
Cotton textiles – China, USA
Commercial vehicles – Mexico, South Africa

Try this.

(I) Obtain the following information.

Question 1.
Make a list of commodities which you use daily.
Answer:
Toothpaste, powder, tea, hair oil, biscuits, food grains.

Question 2.
Who uses these commodities?
Answer:
We as consumers use these commodities.

Question 3.
Write the sources of supplies of these commodities.
Answer:
Producers are the source of supplies.

Question 4.
From where do you buy these commodities?
Answer:
Retail Shop.

Question 5.
What do you call the act of buying and selling?
Answer:
Trade.

Question 6.
What does the shopkeeper take in lieu of the commodity?
Answer:
The shopkeeper takes money (currency) in lieu of the commodity.

(II) A list of few goods you regularly use at home, is given here. Write the names of the product, the producer company’s name and the source of information in front of it.

Goods that Name of the you use	Name of the company	Source of information
Colgate Toothpaste	Palmolive	T.V. advertisement
Coffee Nescafe	Nestle	T.V. advertisement
Bathing Soap Lux	Unilever	T.V. advertisement
Hair Oil Parachute	Marica India	T.V. advertisement
Biscuits Parle G	Parle Products	T.V. advertisement

Choice may vary from consumer to consumer.

(F) Use your brain power! (Textbook Page no. 70) Suppose you are a trader and you want to sell your product in other states of the country and also in other parts of the world

Question 1.
Which of these is an easier way of doing trade?
Answer:
To sell the product in other states of the country, domestic or internal trade is easier. To sell the product in other parts of the world, international trade, i.e. export trade is done

Question 2.
Which trade can bring some limitations?
Answer:
International trade.

Question 3.
Look for reasons behind them
Answer:
Factors like economy of the country, government policis, markets, laws, judicial system, currency, language and political relation between the two trading countries can bring limitations in international trade.

Class 9 Geography Chapter 9 Trade Additional Important Questions and Answers

Complete the statements choosing a colored option from the bracket:

Question 1.
…………………. refers to buying and selling goods and services to fulfill each other’s needs.
(a) Trade
(b) Business
(c) Labelling
(d) Branding
Answer:
(a) Trade

Question 2.
When there is buying and selling of goods it is called ………………….. trade.
(a) invisible
(b) visible
(c) impossible
(d) possible
Answer:
(b) visible

Question 3.
Buying and selling in large quantities is called ………………….. trade.
(a) wholesale
(b) retail
(c) invisible
(d) none of these
Answer:
(a) wholesale

Question 4.
………………….. trade refers to buying and selling in small quantities.
(a) Invisible
(b) Retail
(c) Wholesale
(d) None of these
Answer:
(b) Retail

Question 5.
………………….. trade means buying goods and services from another country
(a) Export
(b) Retail
(c) Wholesale
(d) Import
Answer:
(d) Import

Question 6.
When the value of imports is more than the value of exports it is called ………………….. balance of trade.
(a) favourable
(b) unfavorable
(c) balanced
(d) possible
Answer:
(b) unfavorable

Question 7.
………………….. was formed to control the international trade of crude oil.
(a) OPEC
(b) APEC
(c) ASEAN
(d) WTO
Answer:
(a) OPEC

Question 8.
BRICS stands for …………………. .
(a) Brazil, Russia, Indonesia, China and Sudan
(b) Belgium, Rome, India, China and South Africa
(c) Brazil, Russia, India, China and South Africa
Answer:
(b) Brazil, Russia, India, China and South Africa

Question 9.
………………….. was formed to establish an integrated market2 in member nations in Europe.
(a) EU
(b) ASEAN
(c) BRICS
(d) OPEC
Answer:
(a) EU

Question 10.
………………….. trade means the exchange of goods and services of one country with other countries.
(a) Retail
(b) Wholesale
(c) International
(d) None of these
Answer:
(c) International

Match the following:

Question 1.

Column ‘A’	Column ‘B’
(1) WTO	(a) Brazil, Russia, India, China and South Africa.
(2) BRICS	(b) World Trade Organisation.
(3) Favourable balance of trade	(c) Value of exports is more than value of imports.

Answer:
(1 – b),
(2 – a),
(3 – c)

Question 2.

International organisations	Headquarters
(1) EU (2) WTO (3) SAARC	(a) Kathmandu (Nepal) (b) Jakarta (Indonesia) (c) Geneva (Switzerland) (d) Brussels (Belgium)

Answer:
(1 – d),
(2 – c),
(3 – a)

Question 3.

Column ‘A’	Column ‘B’
(1) OPEC	(a) Expanding social and cultural harmony in South East Asia.
(2) APEC	(b) Controlling international trade of crude oil.
(3) ASEAN	(c) Free trade in Asia- Pacific Ocean region.
	(d) When value of imports is more than the value of exports.

Answer:
(1 – b),
(2 – c),
(3 -a)

Write answers in one sentence each:

Question 1.
What do you mean by trade?
Answer:
Trade refers to buying and selling of goods and services to fulfil each other’s needs.

Question 2.
What is visible trade3?
Answer:
When there is buying and selling of goods it is known as visible trade.

Question 3.
What is invisible trade4?
Answer:
When there is exchange of services, it is known as invisible trade.

Question 4.
Who conducts wholesale trade?
Answer:
Wholesale trade is conducted by wholesalers.

Question 5.
What do you mean by domestic trade?
Answer:
Domestic or internal trade is the trade that takes place within the geographical boundaries of one country. For eg. Trade between Maharashtra and Gujarat.

Question 6.
What is international trade?
Answer:
International trade means buying and selling of goods and services between two or more countries. For example, trade between USA and India.

Question 7.
What do you mean by import trade?
Answer:
Import trade means buying goods and services from another country. For eg. India imports crude oil from Kuwait.

Question 8.
What is export trade?
Answer:
When country sells its goods and services to another country, it is called export trade. For eg. India exports rice to USA.

Question 9.
What is balance of trade?
Answer:
The difference between the import and export values of a country in a specific period is called balance of trade.

Question 10.
What do you mean by unfavourable balance of trade?
Answer:
When the value of imports is more than the value of exports it is called unfavourable balance of trade.

Question 11.
What is favourable balance of trade?
Answer:
When the value of exports is more than the value of imports it is called favourable balance of trade.

Question 12.
What is balanced balance of trade?
Answer:
When the value of exports and imports is almost same, it is called balanced balance of trade.

Question 13.
What is WTO?
Answer:
WTO stands for World Trade Organisation.

Question 14.
What does EU stand for?
Answer:
EU stands for European Union which comprises of 28 European countries.

Question 15.
What does OPEC stand for?
Answer:
OPEC stands for Organisation of Petroleum Exporting Countries.

Question 16.
Give extended form of.
(i) SAARC
(ii) ASEAN
(iii) APEC
(iv) BRICS
Answer:
(i) SAARC – South Asian Association for Regional Co-operation.
(ii) ASEAN – Association of South-East Asian Nations.
(iii) APEC – Asia-Pacific Economic Co-operation.
(iv) BRICS – Brazil, Russia, India, China and South Africa.

Some economic organisations of the world
Maharashtra Board Class 9 Geography Solutions Chapter 9 Trade 3

Give Reason

Question 1.
Some international economic organisations were set up
Answer:
Some international economic organisations were set up:

To smoothen the process of trade between countries of different economic status.
To facilitate the growth of international trade.

Question 2.
The Consumer Protection Act been enacted
Answer:

The Consumer Protection Act has been enacted to protect the consumers from fraudulent traders supplying sub-standard products.
Many advertisements make exaggerated statements to cheat the consumers and these advertisements use incorrect information.
The Consumer Protection Act empowers consumers with their rights and duties. Consumers have right to complain and seek redressal.

Explain the following:

Question 1.
What do you mean by wholesale trade?
Answer:

In wholesale trade, the traders buy goods on a large scale from industrialists, farmers, etc. For eg. the orchard owners of mangoes or oranges sell their entire production to wholesale traders.
The wholesalers in turn sell these commodities to the retail traders.

Question 2.
What is retail trade?
Answer:

The process of buying in small quantities from wholesalers and selling in small quantities to the consumers is called retail trade.
For eg. the shopkeepers selling food grains, vegetable vendors in markets.

Question 3.
What is marketing?
Answer:

An invisible flow develops when a product goes from producer1 to consumer.
The commercial functions involved in this flow are collectively called marketing.

Answer in brief :

Question 1.
Explain the importance of trade.
Answer:
The importance of trade are:

Trade is an important economic activity.
The economic life of people is dependent on each other.
No region or country is self-sufficient.
Trade between two regions is necessary to fulfill the needs of the people.
As each region has different geographical conditions, each region produces specific commodities.

Question 2.
What is barter trade?
Answer:

In ancient and medieval periods, trade was done through barter system.
Barter trade means exchange of commodities for commodities without using money, is a medium.
For eg. grains in exchange of work done or salt exchanged for oil.
But it created the problem of estimating the price of a commodity correctly. As a result, currency started being used.

Question 3.
Mention the functions of the European Union.
Answer:
The main functions of the European Union are:

Establishing an integrated market in member nations amongst Europe.
Free flow of goods, services and capital in Europe.
Custom duties have been cancelled on exchange of goods within members.
Common ‘Euro’ currency for the member countries.

Question 4.
Which factors influence trade?
Answer:
The factors which influence trade are:

Factors like the economy of the country, government policies, markets, laws, judicial systems, currency, language, etc. influence trade.
Political relations between two countries also influence trade between them.

9th Std Geography Questions And Answers:

Std 9 Geography Chapter 1 Question Answer Maharashtra Board

February 4, 2025January 3, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Geography Solutions Chapter 1 Distributional Maps Notes, Textbook Exercise Important Questions and Answers.

Distributional Maps Class 9 Questions And Answers Maharashtra Board

Class 9 Geography Chapter 1 Distributional Maps Questions And Answers Maharashtra Board

Geography Class 9 Chapter 1 Question Answer Maharashtra Board

1. Give reasons why the following sentences are right or wrong:

Geography Class 9 Chapter 1 Distributional Maps Question 1.
The main aim of distributional maps is to show location.
Answer:
Wrong The main aim of distributional maps is to show the distribution of variables like temperature, rainfall, population, etc.

Distribution maps are type of thematic maps.
These maps are prepared with special themes like the distribution of various variables in a particular region.
They make use of different methods to show the distribution of variables like temperature, rainfall, population, etc.

Thus, the main aim of distributional maps is to show the distribution of variables in a particular region.

Distributional Maps Class 9 Question 2.
In choropleth maps, only one value is assigned to the sub-administrative unit.
Answer:
Right

In choropleth maps, the data regarding various geographical variables is shown by shading or using tints of various colours.
After gathering the data for a selected variable, five to seven classes are made considering the smallest and the largest values.
Each class is assigned a tint of the same colour or black-and-white patterns.
A particular value shown by a predecided tint of colour can represent only a particular region or group of region.

Thus, in choropleth maps, only one value is assigned to sub administrative unit.

Distributional Maps Questions And Answers Question 3.
In choropleth maps, colours/tints do not change according to the values of the variables.
Answer:
Wrong.
In choropleth maps, colours/tints change according to the values of variables.

In choropleth maps, the smallest and the largest values are taken into consideration and after that 5-7 classes are made.
Each class is assigned a unique tint of the same colour or black and white pattern.
In other words, each class is used to show the distribution of a particular variable in sub- administrative unit.

Distributional Map Question 4.
Choropleth maps are used to show altitudes.
Answer:
Wrong.
Isopleth maps and not the choropleth maps are used to show altitude.

When the distribution of a variable is continuous like the altitude, the isopleth method map is used.
Isopleth maps use lines joining the locations having equal values and hence are useful to show the change in altitude in the region.
When the distribution of a variable is discontinuous, the choropleth method map is used to show its distribution, eg. distribution of population, domestic animals, etc.

Question 5.
Isopleth maps are used to show population distribution.
Answer:
Wrong.
Dot method maps or choropleth method maps are used to show population distribution

Distribution of a population is discontinuous.
Isopleth method maps are used to show the distribution of variables which are continuous. For eg. altitude, temperature etc.
Thus, isopleth method maps are not used to show population distribution.

Question 6.
In dot method, every dot should have an appropriate scale.
Answer:
Right.
The size of the dot is decided as per the value of a variable that is freely scattered across the region.

Question 7.
Isopleth maps are not made using isolines.
Answer:
Wrong.
Isopleth maps are made using isolines.

Isolines are lines joining places of same values of a given variable in a map.
Since, isopleth maps are also prepared in the same method, we can say that they are made using isolines.

Question 8.
Distribution of various geographical elements can be shown using dot method.
Answer:
Wrong.
Distribution of various geographical elements cannot be shown using dot method.

Distribution of geographical elements which are freely scattered across a region can be shown using a dot method.
Distribution of variables like population, minerals, cattles etc., are freely scattered hence can be shown on a dot method map.
Whereas the distribution of variables like rainfall, altitude, temperature etc. which are continuous, cannot be shown using a dot method map.

2. Answer in brief.

Question 1.
Explain the use and types of distributional maps.
Answer:
(a) Use of distributional maps: The distributional maps are useful for explaining the patterns of distribution of a particular geographical variable.
(b) The types of distributional maps : The following are the types of distributional maps.

Dot Method: The distributional map based on statistical data, made by this method, make use of dots of a pre-decided size to show the distribution of a particular variable, e.g. Dot method map is used to show the population of a region, distribution of cattle etc.
Choropleth Method: The distributional map made by this method makes use of shades or tints of various colours, to show the distribution of a particular variable, e.g. Choropleth method map is used to show population density, types of forest cover, uses of land.
Isopleth Method: The distributional map made by this method makes use of lines joining locations or places having same or equal values of a particular variable, e.g. Isopleth method map is used to show altitude, temperature, rainfall.

Question 2.
Differentiate between choropleth and isopleths methods.
Answer:

Choropleth Method	Isopleth Method
(1) In Choropleth method maps, the distribution of various variables are shown by shading or using tints of the same colour.	(1) In Isopleth method maps, the distribution of various variables are shown with the help of isolines.
(2) When the distribution of a variable is not continuous, the choropleth method is used.	(2) When the distribution of a variable is continuous, the isopleth method is used.
(3) Choropleth method is used to show population density, cattle distribution etc.	(3) Isopleth method are used to show altitude, temperature, rainfall of a region etc.

Question 3.
Explain with reasons the method which is best suited to show the distribution of population in a region.
Answer:

The dot method of making a distributional map is best suited to show the distribution of the population in a region.
The dots used in this method, are given a particular value which is determined by selecting a proper scale considering the spread of the values of the variables in the given region.
This method is best suited to show the distribution of the variables which are freely scattered as in the case of population distribution.

3. Which method will you use for the following information?

Question 1.
Talukawise wheat production in the district
Answer:
Dot method

Question 2.
Distribution of the altitude of the land in the district.
Answer:
Isopleth method

Question 3.
Distribution of domestic animals in the State
Answer:
Dot method

Question 4.
The distribution of population density in India
Answer:
Choropleth method

Question 5.
Temperature distribution in Maharashtra State.
Answer:
Isopleth method

4. Study the population distribution map of Kolhapur district and answer the following questions:

Question 1.
Which method has been used to show the distribution of population in the district?
Answer:
The dot method has been used to show the distribution of population in the district.

Question 2.
Explain the direction wise distribution of the population from dense to sparse.
Answer:
The distribution of the population is dense in the Eastern part of the district, whereas the western part of the district has low density of population.

Question 3.
What is the population shown by the largest circle? Which place is that?
Answer:
The population shown by the largest circle is nearly 20 lakhs. That place is Kolhapur city (Karvir Taluka)

Question 4.
Which Taluka has the least population?
Answer:
Gaganbavada Taluka has the least population.

Class 9 Geography Chapter 1 Distributional Maps Intext Questions and Answers

Make friends with maps!
Read the map given below and answer the Questions:
Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 2

Question 1.
What is the population of the Amravati town?
Answer:
The population of the Amravati town is nearly 5 lakhs.

Question 2.
Name the place having population of 1 lakh on the map.
Answer:
Achalpur has a population of 1 lakh

Question 3.
Which part of the map shows sparse distribution of population?
Answer:
The northwestern part of the map shows sparse distribution of population

Read the map given below and answer the Questions:
Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 3

Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 4

Question 1.
Name the talukas having population density between 301 and 400 persons per sq km.
Answer:
Anjangao Surji has population density between 301 and 400 persons per sq km

Question 2.
What is the density of the Amravati taluka?
Answer:
Amravati taluka has the population density of more than 400 persons per sq km

Question 3.
Name the talukas having population density less than 300 persons per sq km.
Answer:
Dharini, Chikaldhara, Daryapur, Chandur Bazar, Morshi, Varud, Tivsa, Dhamangaon Railway, Nandgaon Khandeshwar and Bhatkuli have population density less than 300 persons per sq km.

Question 4.
Which taluka has a population density of less than 100 persons per sq km?
Answer:
Chikaldhara has population density of less than 100 persons per sq km.

Question 5.
Which Talukas have a population density of more than 400 persons per sq km?
Answer:
Amravati and Achalpur have the population density of more than 400 persons per sq km.

Read the map given below and answer the Questions:

Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 5

Question 1.
In which part of the district is the rainfall more?
Answer:
Rainfall is more in the Northern part of the district.

Question 2.
In which direction is the rainfall decreasing?
Answer:
Rainfall is decreasing towards the west

Question 3.
What is the lowest value of the rainfall in the district?
Answer:
The lowest value of the rainfall in the district is less than 800 mm.

Question 4.
What is the highest value of the rainfall in the district?
Answer:
The highest value of the rainfall in the district is more than 1300 mm.

Question 5.
What is the amount of rainfall in the central part of the district?
Answer:
The amount of rainfall in the central part of the district is 900 mm.

Read the map given below and answer the Questions:

Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 6

Question 1.
In which direction is the density of population decreasing?
Answer:
The density of population is decreasing towards the North and South direction.

Question 2.
Name the talukas with a population density less than 200.
Answer:
Shahuwadi, Gaganbavada, Ajra and Chandgad have a population density of less than 200.

Question 3.
Name the talukas having population density between 200 and 400.
Answer:
Radhanagri and Gargoti have population density between 200 and 400.

Question 4.
Name the talukas with a population density more than 400.
Answer:
Kolhapur, Panhala, Hatkanangale, Shirol, Gadhinglaj and Kagal have population density more than 400.

Question 5.
In which direction are the talukas having a higher density of population located in the district?
Answer:
The Eastern part of Kolhapur has a higher density of population.

Question 6
Which method has been used in the making of this map?
Answer:
Choropleth method is used in making this map.

Read the map given below and answer the Questions:

Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 7

Question 1.
In which direction is the rainfall more in the district?
Answer:
The rainfall is more in the Western part of the district.

Question 2.
In which direction is the rainfall decreasing?
Answer:
The rainfall is decreasing towards the East.

Question 3.
Which class shows low rainfall category in the district?
Answer:
O to 600 mm class shows low rainfall category in the district.

Question 4.
Which class shows high rainfall category in the district?
Answer:
More than 2400 (2400 to 3000 mm) class shows high rainfall category in the district.

Question 5.
Which method has been used in making this map?
Answer:
The Isopleth method has been used in making this map

Study the population distribution map of Kolhapur district and answer the following questions:

Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 8

Question 1.
A field visit is an important study method in Geography.
Answer:
Right.

Geographical concepts and elements can be directly experienced through field-visits.
Field-visits are extremely useful for understanding the correlation between human beings and the environment.

Class 9 Geography Chapter 1 Distributional Maps Additional Important Questions and Answers

Complete the statements choosing the correct option:

Question 1.
The main aim of distributional maps is to show the location of the place and of variables.
(a) population
(b) statistics
(c) consumption
(d) distribution
Answer:
(d) distribution

Question 2.
Distributional maps are of types.
(a) two
(b) three
(c) four
(d) five
Answer:
(b) three

Question 3.
To draw distributional maps, we need data.
(a) statistical
(b) population
(c) colourful
(d) distance
Answer:
(a) statistical

Question 4.
The distribution of population is shown by method.
(a) dot
(b) choropleth
(c) isopleth
(d) isolines
Answer:
(a) dot

Question 5.
In maps, the data regarding various geographical variables are shown by shading or tints of various colours.
(a) dot
(b) choropleth,
(c) isopleth
(d) thematic
Answer:
(b) choropleth

Question 6.
When the distribution of a variable is discontinuous the map is used.
(a) isopleth
(b) physical
(c) choropleth
(d) dot
Answer:
(c) choropleth

Question 7.
In method, lines showing equal values are used.
(a) choropleth
(b) isopleth
(c) dot
(d) planar
Answer:
(b) isopleth

Question 8.
When the distribution of a variable is the isopleth method is used.
(a) continuous
(b) discontinuous
(c) sparse
(d) disjoint
Answer:
(a) continuous

Question 9.
While showing population distribution, urban population is shown by
(a) circles
(b) dots
(c) squares
(d) lines
Answer:
(a) circles

Question 10.
is an important study method in Geography.
(a) Maps
(b) Field visit
(c) Picnic
(d) farm visit
Answer:
(b) Field visit

Match the column.

Question 1.

Group A	Group B
(1) Dot method	(a) distribution of temperature
(2) Choropleth method	(b) distribution of cotton crop
(3) Isopleth method	(c) density of population

Answer:
(1 – b),
(2 – c),
(3 – a)

Question 2.

Group A	Group A
(1) Dot method (2) Choropleth method (3) Isopleth method	(a) variables are freely scattered (b) distribution of the variable is continuous (c) distribution of the variable is shown in sub administrative unit

Answer:
(1 – a),
(2 – c),
(3 – b)

Answer in one sentence:

Question 1.
What are distributional maps?
Answer:
Maps that show the distribution of various geographical variables are called ‘distributional maps’.

Question 2.
What are thematic maps?
Ans,
Maps that are prepared with special themes are called ‘thematic maps’.

Question 3.
What is a dot-method map?
Answer:
A dot method map is a map type, that shows the distribution of a variable using dot symbols.

Question 4.
What is a choropleth method map?
Answer:
A choropleth method map is a map type, in which the distribution of a variable is shown by shades or tint of various colours.

Question 5.
When do we use the isopleth method for showing the distribution of a variable on a map?
Answer:
We use the isopleth method for showing the distribution of a variable on a map, when the distribution of the variable is continuous.

Question 6.
What is an isopleth method map?
Answer:
An isopleth method map, is a map type, that shows distribution of a variable with the help of lines showing equal values.

Question 7.
What is point related data?
Answer:
The statistical data of particular variables with respect to various places is called ‘point-related data’.

Question 8.
Which elements are generally studied in a geographical field visit?
Answer:
The various elements which can be studied during geographical field visits include physical landforms, river banks, dams, coastal areas, tourism sites, offices or museums related to geographical elements, villages, forest areas etc.

Question 9.
Mention the list of things to be carried while going on a geographical field visit?
Answer:
The various things which one should carry to a geographical field visit include notebook, specimen Questionnaire, pen pencil, scale, tape, compass, bag for collecting samples, maps, camera, etc.

Question 10.
What is field report?
Answer:
The report written on the basis of the information obtained from a field visit is known as field report.

Which method will you use for the following information:

Question 1.
The distribution of rainfall in the district of Nandurbar.
Answer:
Isopleth Method

Question 2.
Cotton crop distribution in Maharashtra.
Answer:
Dot method

Question 3.
Draw a map using the Dot Method:
Answer:
Maharashtra Board Class 9 Geography Solutions Chapter 1 Distributional Maps 1

Explain:

Question 1.
Choropleth method
Answer:

In the choropleth method various geographical variables are shown by shades or tints of various colours.
While making choropleth maps, the data used for different variables is obtained through various processes such as measurement, surveying and so on.
In this method, only one value is given to one sub – administrative unit in a region
The smallest and the largest values of the given data of the variables are taken into consideration and after that 5-7 classes are made.
Each class is assigned a tint of the same colour or black-and-white patterns. The shades or the patterns become darker with the increasing values of the given variable.

Question 2.
Preparations for field visit
Answer:

Before going for a field-visit, decide the place and the purpose of the visit.
The elements which will be observed in field visit should be decided.
For a field visit, you should carry a notebook, specimen Questionnaire
, pen, pencil, scale, tape, compass, a bag for collecting samples, maps, camera and any other item needed.

Question 3.
Selection of the study area
Answer:

Geographical field-visit is organised for study of various elements, for example physical 1 landforms, river banks, dams, coastal areas, tourism sites, offices or museums related to ! geographical elements, villages or forest areas.
Elements should be selected after studying : the local conditions and necessary permission letters should be obtained.

Question 4.
Report writing
Answer:

A field-report should be written on the basis of information obtained after the visit is complete.
Students should add photographs wherever necessary.
The following points should be used to make a field report:
- Introduction
- Location map and Route Map
- Physiography¹
- Climate
- Population
- Environmental problems and measures
- Land utilisation
- Conclusions

9th Std Geography Questions And Answers:

Std 9 Geography Chapter 5 Question Answer Maharashtra Board

February 4, 2025January 3, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Geography Solutions Chapter 5 Precipitation Notes, Textbook Exercise Important Questions and Answers.

Precipitation Class 9 Questions And Answers Maharashtra Board

Class 9 Geography Chapter 5 Precipitation Questions And Answers Maharashtra Board

Geography Class 9 Chapter 5 Question Answer Maharashtra Board

1. Identify the precipitation type with the help of the description given:

(a) It is the main source of the water that you use. Sometimes it is torrential and sometimes continuous. Most of the agriculture in India is dependent on it.
(b) It seems as if water droplets are floating in the atmosphere. In London, one cannot see the Sun till the afternoon during winters because of this phenomenon.
(c) It never precipitates like this in equatorial areas. Precipitation in the solid form sometimes causes damage to the crops.
(d) A white cotton-like layer spreads on the earth’s surface. Because of this form of precipitation, the State of Jammu and Kashmir has to change its capital in winters. In Maharashtra, it does not precipitate like this.
Answer:
(a) rainfall
(b) fog
(c) hail
(d) snow

2. Look at the following pictures and identify the correct rainfall type.
Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 1
Answer:
Convectional rainfall

Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 6
Answer:
Orographic rainfall

Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 7
Answer:
Cyclonic rainfall

3. Look at the figures above and answer the following questions:

Question 1.
In fig B, on which side of the mountain is it raining more?
Answer:
The windward side is receiving more rainfall.

Question 2.
Shade the rain shadow region in fig B and name it.
Answer:
Students to show the leeward side in the picture.

Question 3.
What is the difference between A and C?
Answer:
In figure 5.4 i.e. convectional rainfall the hot air rises upwards and then the air cools and begins to condense and due to continuous condensation rainfall occurs. Here rainfall is accompanied by lightning and thunder.

In figure 5.6 , i.e. cyclonic rainfall, air from surrounding regions comes towards the centre of the cyclone and starts moving upwards. As it rises, the temperature of the air reduces, condensation occurs and rainfall takes place.

Question 4.
Stormy winds and floods are associated with which rainfall type?
Answer:
Stormy winds and floods are associated with Cyclonic rainfall.

Question 5.
What type of rainfall occurs in Singapore?
Answer:
Cyclonic rainfall occurs in Singapore.

4. Identify the odd man out:

Question 1.
Orographic rainfall, acid rain, cyclonic rainfall, convectional rainfall
Answer:
Acid rain

Question 2.
Snowfall, rainfall, hailstones, dew
Answer:
Dew

Question 3.
Thermometer, rain gauge, anemometer, measuring jar
Answer:
Measuring jar

5. Answer in brief:

Question 1.
In what ways does precipitation occur on the earth?
Answer:
Precipitation means water falls in the solid or liquid state from the clouds to the earth surface. Snow, hailstorms, rainfall are the major forms of precipitation.

(i) Snow:
Answer:

When the temperature in the atmosphere falls below the freezing point the water vapour directly turns into snowflakes. This is called sublimation.
Hence the vapour in the form of gas transform into solid snow. Precipitation in the form of solid particles is known as snowfall.
As snow is in the solid form. It does not run like water and layers of the snow get deposited on the top of the others and when the snow melts the region gets fresh water.

(ii) Hail:

When there is lot of heat on the earth’s surface, the upward air flow blows at a greater speed. Because of this upward flow, the temperature of air reduces and the condensation of the water vapour takes place, and dark clouds are formed.
Because of the upward movement of the air, these water droplets go at higher altitude and solidify forming hailstones.
As the hailstones are heavy, they fall toward the earth’s surface because of gravity. The crops may get destroyed and loss of life and property may occur.
Hailstones occurs in summer in India, Africa and in some parts of south east Asia.

(iii) Rainfall:

We get water generally in the form of rainfall. The temperature of the air with water vapour reduces when it goes higher and condensation of the vapour occurs.
Clouds formed with the condensed water droplets and dust particles accumulate.
As these water droplets increase in the size, they cannot float in the air anymore because of their weight. They come down as rainfall
The different types of rainfall are: Convectional rainfall, Orographic rainfall and Cyclonic rainfall.

(iv) Fog, dew and frost:

When the condensation or solidification of the water vapour in the atmosphere occurs near the earth’s surface, it leads to the formation of fog, dew and frost.

Question 2.
Comment on the rainfall occurring in the rain shadow area.
Answer:

The winds coming from lakes or seas are moisture-laden and they are obstructed by the high mountain ranges coming in their way
They start going upwards along the slope of the moutains. The temperature of these winds drop and condensation occurs and rainfall takes place.
This rainfall takes place because of the obstruction of the mountains which results in the condensation of water vapour.
The windward side of the mountain gets more rain; the amount of vapour in the air reduces after crossing the mountain and the moisture-holding capacity of the air increases.
The leeward side of the mountain gets lesser rainfall as compared to windward side.
Thus, the leeward side area is identified as rain shadow area as it recieves meagre rainfall.

Question 3.
Which type of rainfall occurs in most of the world? Why?
Answer:

Orographic rainfall occurs in most parts of the world.
Convectional rainfall is regional in nature.
There is a certainty in the convectional rainfall occurring in the equatorial areas.
Comparatively, the orographic and cyclonic rainfall is less certain.
And therefore, such areas are prone to very heavy rainfall, floods or droughts frequently.

Question 4.
If condensation occurs closer to the earth’s surface, what types of forms become visible?
Answer:
If condensation and solidification of the water vapour in the atmosphere closer to the earth surface are visible, they are in the form of fog, dew or frost.

(i) Fog:

The temperature of the layers of the air near the surface of the earth reduces. As the temperature reduces, water vapour condenses.
In this process the water vapour turns into microscopic water particles and float in the air.
When the density of these droplets in the air increases it leads to the formation of fog

(ii) Dew:

When moisture-laden air near the earth surface comes in contact with very cold objects condensation of water vapour takes place.
They turn into very small water droplets and stick to the surface of cold objects, e.g. eg: leaves and this is called dew.

(iii) Frost:

When the temperature of the air reaches less then 0 degree Celcius the water droplet stuck to the surface of the cold objects and freezes.
This frozen water droplet is called as frost.

Question 5.
What precautions should be taken while measuring rainfall?
Answer:

Rainfall is an important source of water on planet earth and rainfall is formed because of changes in the temperature of the air with water vapour.
The instrument that is used to measure rainfall is called rain gauge.
The funnel i.e. used for measuring rain has a specific diameter and the rain falling in this funnel is collected in bottle fitted in the gauge.
The collected water is then measured with the help of measuring jar. In the areas of heavy rainfall, the reading of the rain with rain gauge should be taken every three hours. The measuring jar reads rain in millimetres
The gauge has to be kept on open ground on 30cm high flat-mount.
So that the rain water is collected without any obstruction.

6. Distinguish between

Question 1.
Dew and frost
Answer:

	Dew		Frost
(i)	When moisture-laden air near the earth’s surface comes into contact with very cold objects, condensation of vapour takes place into small water droplets called dew.	(i)	If the temperature of the air is less then CPC, the water droplets stuck to the surface of cold objects, freezes forming frost.
(ii)	Water vapour condenses and forms droplets of water.	(ii)	Water droplets stuck to cold surface turns to frozen water droplets.
(iii)	Dew sticks to the cold object but does not freeze.	(iii)	It sticks to the cold object and freeze.

Question 2.
Snow and hail
Answer:

	Snow		Hail
(i)	Precipitation in the form of solid particles of snow is known as snow fall.	(i)	Precipitation in the form of frozen water droplets falling rapidly to the ground is know as hail.
(ii)	The fall of temperature in the atmosphere below the freezing point causes snow fall	(ii)	Extreme heat on the surface of the earth initiates the process of hail formation.
(iii)	Heavy accumulation of snow can collapse the transportation and communication system of the area.	(iii)	It destroys crops and causes loss of life an

Class 9 Geography Chapter 5 Precipitation Intext Questions and Answers

Can you tell?

Question 1.
The blade of grass look like this in winter mornings. From where does the water on the blades of grass come?
Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 8
Answer:

The blade of grass looks like this in winter mornings because of dew. These are small water droplets.
The dew is formed in winter because moisture-laden air near the earth surface comes in contact with cold objects due to which condensation of vapour takes place, turning into small water droplets.

Question 2.
Snow is found everywhere in the winters in Kashmir.
Answer:
Snow is found everywhere in winters of Kashmir because Kashmir is located at a higher altitude where the temperature falls below freezing point. Hence water vapour directly turn into snowflakes leading to snowfall.

Question 3.
Why isn’t snow found in our surroundings?
Answer:
Because we have a moderate temperature and we are closer to the sea, snow is not found in our surroundings.

Question 4.
Generally, it rains between June and September in our region.
Answer:
We get rainfall between June and September, in our region when the moisture-laden south-west monsoon winds are obstructed by the Western Ghats leading to orographic rainfall.

Question 5.
How do the rain droplets form?
Answer:
Clouds form when condensed water droplets and dust particles accumulate forming large rain droplets.

Question 6.
In London, there is a fog like this till the afternoon in the winters.
Answer:
In London there is fog till the afternoon in winters because London is far away from equator and it has temperate oceanic climate and they have cool summers.

Question 7.
We do not have fog until afternoons in summers.
Answer:
We do not have fog until afternoons in summer because we are near to equator and we have tropical climate and hot summers.

Question 8.
Sometimes hailstones destroy the standing crops in the field.
Answer:
Hailstones are solid and heavy in nature and they hit the earth due to gravity and this is the reason they destroy the crops in the field.

Question 9.
Why don’t we get hailstones frequently?
Answer:
For the formation of hailstones the following 2 conditions are required:

Intense heating which results in upwards air flow.
The decrease in air temperature at higher layers of the atmosphere.
As India is a tropical country, we do not find cooler air at higher levels because of the intense heating of land.

Think about it.

Question 1.
We use a raincoat or umbrella to protect ourselves from rainfall. What will you use to protect yourself from severe hailstorms?
Answer:
If a person is outside without any coverage, he needs to seek shelter immediately, making sure to protect his head from hailstones.

Question 2.
Because of the conventional processes, convectional rainfall occurs in the afternoon in equational areas. But why doesn’t it rain in afternoons in the oceanic areas of the equatorial belt?
Answer:
One of the necessary conditions of convectional rainfall is intense heating of surface which causes air to expand and rise. Since land heats up faster than water, it rains only on the land in the equatorial regions and not in the oceanic areas.

Question 3.
Why are the areas of high rainfall situated in tropical areas?
Answer:

Tropical areas receive direct rays of the Sun almost throughout the year. Hence the rate of evaporation1 is high here.
The tropical region receives convectional rainfall throughout the year and also orographic rainfall is experienced here.
Thus areas of high rainfall are situated in the tropical area.

Class 9 Geography Chapter 5 Precipitation Additional Important Questions and Answers

Complete the statements choosing the correct option from the bracket:

Question 1.
……………. part of the earth’s surface is full of water.
(a) 30.7%
(b) 4.09%
(c) 60.5%
(d) 70.8%
Answer:
(d) 70.8%

Question 2.
When the temperature in the atmosphere falls below the freezing point and the water vapour directly turns into snowflakes, the process is called as ……………..
(a) sublimation²
(b) frostbite³
(c) carbonation
(d) convection
Answer:
(a) sublimation

Question 3.
In areas located at higher altitudes and high latitudes, where the temperatures are below 0°C get precipitation in the form of ………….
(a) dew
(b) rain
(c) snow
(d) hail
Answer:
(c) snow

Question 4.
Because of ………………. crops may get destroyed and loss of life and property may occur.
(a) dew
(b) rain
(c) snow
(d) hail
Answer:
(d) hail

Question 5.
Hails do not occur in ……………… areas.
(a) temperate
(b) equatorial
(c) landlocked
(d) mountainous
Answer:
(b) equatorial

Question 6.
In equatorial areas, …………. type of rainfall occurs almost daily in the afternoons.
(a) frontal
(b) convectional
(c) cyclonic
(d) orographic
Answer:
(b) convectional

Question 7.
…………… rainfall occurs because of obstruction from high mountain ranges.
(a) Frontal
(b) Convectional
(c) Cyclonic
(d) Orographic
Answer:
(d) orographic

Question 8.
Cyclonic rainfall occurs more in …………… zones.
(a) temperate
(b) equatorial
(c) torrid
(d) polar
Answer:
(a) temperate

Question 9.
…………… rainfall occurs in most of the parts in the world.
(a) Frontal
(b) Convectional
(c) Orographic
(d) Cyclonic
Answer:
(c) orographic

Question 10.
Snowfall can also be measured with the help of ……………
(a) hygrometer
(b) rain gauge
(c) barometer
(d) anemometer
Answer:
(b) rain gauge

Question 11.
A layer of ice is equivalent to 10mm of rainfall.
(a) 10mm
(b) 50mm
(c) 100mm
(c) 120mm
Answer:
(c) 120mm

Question 12.
When moisture-laden air near the earth’s surface comes in contact of very cold objects and form water droplets which stick to the surface of the cold objects is formed.
(a) dew
(b) frost
(c) hail
(d) fog
Answer:
(a) dew

Question 13.
If the temperature of the air reaches less than 0°C, the water droplets stuck to the surfaces of cold objects freeze and form
(a) dew
(b) frost
(c) hail
(d) fog
Answer:
(b) frost

Question 14.
If precipitation does not take place, then conditions of arise.
(a) floods
(b) hail
(c) snowstorm
(d) drought
Answer:
(d) drought

Question 15.
Visibility reduces because of
(a) floods
(b) drought
(c) fog
(d) dew
Answer:
(c) fog

Match the column:

Question 1.

Column A	Column B
(1) Snowflakes	(a) upward air flow
(2) Hailstones	(b) sublimation
(3) Dew	(c) microscopic water particles floating in the air
(4) Fog	(d) condensation⁴ on cold objects

Answer:
(1 – b),
(2 – a),
(3 – d),
(4 – c)

Question 2.

Column A	Column B
(1) Orographic rainfall (2) Convectional Rainfall (3) Cyclonic Rainfall	(a) Daily in equatorial areas (b) More in temperate zones (c) Mountain barrier

Answer:
(1 – c),
(2 – a),
(3 – b)

Answer in one sentence:

Question 1.
What percentage of the earth’s surface is covered with water?
Answer:
70.8% of the earth’s surface is covered with water.

Question 2.
Why do we see different forms of condensation?
Answer:
Different forms of condensation are seen due to changes in atmospheric conditions.

Question 3.
What is precipitation?
Answer:
When water falls in the solid or liquid state from the clouds to the ground, it is called as precipitation.

Question 4.
Name the major forms of precipitation.
Answer:
Snow, hailstones and rainfall are the major forms of precipitation.

Question 5.
Explain the process of sublimation.
Answer:
When the temperature in the atmosphere falls below the freezing point, water vapour directly turns into snowflakes this process is called sublimation.

Question 6.
In India, hails occur in which season?
Answer:
Hails occur in summer reason in India.

Question 7.
Why don’t hails occur in cold zones?
Answer:
Hails do not occur in cold zones because of lack of upward flow.

Question 8.
Why don’t hails occur in equatorial areas?
Answer:
Hails do not occur in equatorial areas because of the heat in the atmosphere.

Question 9.
Which type of rainfall occurs because of obstruction of mountain?
Answer:
Orographic rainfall occurs because of obstruction of mountains.

Question 10.
Convectional rainfall is mainly experienced in which region?
Answer:
Convectional rainfall is mainly experienced in equatorial region.

Question 11.
What is a Cyclone?
Answer:
Cyclone is a specific air formation when the pressure at an area is less than the surrounding regions.

Question 12.
What is acid rain?
Answer:
Precipitation of water with dissolved acids is called acid rain.

Study the rainfall map of the world given below and answer the following question:
Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 3
Question 1.
Which region experiences more rainfall?
Answer:
The tropical region experiences more rainfall.

Question 2.
What is the reason for low rainfall in the Central Peninsular India?
Answer:
The Central Peninsular India falls on the leeward side of the Western Ghats and hence a rain shadow region is formed here.

Question 3.
Why does the eastern part of Central African continent gets less rainfall than the western part despite its location close to the equator?
Answer:

Eastern part of the African Continent is a rain shadow region of westerly monsoon winds whereas the western part lies on the windward side and gets more rain.
The eastern part of Africa also comes under the influence of the North east trade winds but still receive less rains as they are dry winds originating from the land.

Question 4.
Why does the amount of high rainfall in the western part of the European continent reduce in the eastern part?
Answer:
There are many mountain ranges in the western part of Europe. These obstruct the rain-bearing clouds coming from the west and therefore the amount of rainfall received is high in the west and it reduces towards the east.

Question 5.
Why is rainfall more only in the eastern coast of Australia?
Answer:
The eastern part of Australia is a mountainous region. The winds blowing from the Pacific Ocean are obstructed by these mountains resulting in orographic rainfall towards the east and the formation of a rain shadow zone towards the west.

Observe the horizontal profile of Maharashtra in the following figure and answer the following questions:
Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 4
Question 1.
What type of rainfall occurs in Maharashtra?
Answer:
Orographic rainfall occurs in Maharashtra.

Question 2.
Where will the rain shadow area lie in Maharashtra?
Answer:
The rain shadow area lies to the Leeward side of Sahyadri hills (Maharashtra plateau).

Question 3.
Think about the figure and estimate the rainfall of your district.
Answer:
The answer may vary.

Give reasons:

Question 1.
Crops may get destroyed due to hailstones.
Answer:

As hailstones are heavy they fall towards the earth’s surface, but because of the frequent upward flow of air, they are repeatedly taken upwards.
Here, a new layer of snow encapsulates the hail. This happens quite a few times.
Hence, concentric layers are formed while the hail grows in size.
These big heavy hailstones fall rapidly to the ground because of gravity. This type of precipitation is called as hail.
Hence due to hail, crops may get destroyed.

Question 2.
There is a difference between ice and snow.
Answer:

In areas located at higher altitudes and high- latitudes, where the temperatures are below 0°C get precipitation in the form of snow.
Snow is friable and opaque. This snow accumulates in the form of layers on top of each other.
Because of the pressure from the upper layers, the lower layers of the snow become homogeneous, massive and transparent.
Massive transparent snow formed in such a way is called ice.

Thus, there is a difference between ice and snow.

Question 3.
In equatorial areas, convectional rainfall occurs almost daily in the afternoons.
Answer:

In equatorial areas, the surface gets heated because of the sun’s heat and the air near it also gets heated.
As it gets heated, it spreads and becomes lighter and moves upwards. It cools down when it goes upward. The moisture-holding capacity of cold air is less.
Consequently, condensation of the water vapour occurs and rainfall occurs in equatorial areas.
Thus in equatorial areas, convectional rainfall occurs almost daily in the afternoons.

Question 4.
A rain shadow area is formed on the leeward side of the Western Ghats.
Answer:

Winds coming from Arabian sea are moisture-laden. They are obstructed by the Western Ghats coming in their way.
According to the slope of the Western Ghats, the moisture-laden winds start going upwards.
The temperature of these winds drop and condensation occurs and rainfall takes place. Thus, because of the obstruction of the Western Ghats, orographic rainfall occurs.
The windward side of the mountains gets more rain; amount of vapour in the air reduces after crossing the mountain and the water vapour carrying capacity of the air increases.
The leeward side of the mountain gets lesser rainfall and hence a rain-shadow area is formed here.

Question 5.
Snowfall is not experienced in Maharashtra.
Answer:

Solid snow particles are formed in regions where the temperature falls below the freezing point leading to the process of sublimation.
In the sublimation process, the water vapour directly turns into snowflakes.
In Maharashtra, during winters the temperature never falls below the freezing point.
Hence snowflakes are never formed in the atmosphere.
Thus snowfall is not experienced in Maharashtra.

Question 6.
Hailstones do not occur frequently.
Answer:

Strong vertical movements of air with very high difference in temperature are an ideal condition for the formation of hailstones.
Presence of moisture is also necessary in the air.
Such conditions do not exist frequently.
Hence hailstones are not experienced frequently.

Question 7.
Dew and frost occur on a large scale in winters.
Answer:

During winters when moisture-laden air near the earth’s surface comes in contact very cold objects, condensation of the vapour takes place.
They turn into very small water droplets. These water droplets get stick to the surface of the cold objects. This is called dew.
If the temperature of the air is less than 0°C, the water droplets stuck to the surfaces of cold objects freeze.
This frozen water droplet is called frost.
Thus dew and frost occur on a large scale in winters.

Draw diagram of Rain Gauge:
Answer:
Maharashtra Board Class 9 Geography Solutions Chapter 5 Precipitation 5

Question 6.
Explain the effects of precipitation.
Answer:

The main source of potable water available on the earth is precipitation.
As extreme rainfall is destructive so is the absence of rainfall.
Floods may occur because of heavy rainfall and causes loss to life and property.
If precipitation does not take place then conditions of drought arise. It causes a shortage of food and food may have to be imported and farmers’ conditions becomes grave.
The economy of an agrarian1 country like India is dependent on agriculture. The agriculture in India to a large extent is dependent on monsoons. Hence rainfall in India is important to the whole country.
A good rainfall at the right time increases crop production while untimely rain can damage the crope.
Acid rains which is a combination of harmful gases and rainwater is harmful to the living organisms as well as non-living objects.

Explain:

Question 1.
Snowfall
Answer:

When the temperature in the atmosphere falls below the freezing point, the water vapour directly turns into snowflakes. This is called sublimation.
Here, the vapour in the form of gas transforms into solid snow.
Precipitation in the form of solid particles is known as snowfall.
In high latitudinal and temperate regions, snowfall occurs at the mean sea level while in tropical areas, snowfall occurs at places located higher than the snowline altitude.

Question 2.
Formation of hailstones.
Answer:

When there is a lot of heat on the earth’s surface, the upward air flow blows at a great speed.
Because of this upward flow, the temperature of the air reduces and the condensation of the water vapour takes place.
Dark clouds are formed. Because of the upward movement of air, these water droplets go at a higher altitude.
Here, solidification of these droplets occur and hailstones are formed.

Question 3.
Cyclonic rainfall
Answer:

Cyclone is the specific air formation when the pressure at an area is less than the surrounding regions.
Air from the surrounding region comes toward the center of the cyclone and starts moving upwards.
As it rises, the temperature of the air reduces, condensation occurs and rainfall takes place.
It rains in areas over which the cyclone passes. Cyclonic rainfall occurs more in temperate zones and its area is also quite extensive.
Comparatively, cyclonic rainfall occurring in tropical regions is limited in extent and is stormy in nature.

Question 4.
Rain Gauge.
Answer:

The instrument that is used to measure rainfall is called rain gauge.
The funnel that is used for measuring rain has a specific diameter. The rain falling in this funnel is collected in a bottle fitted in the gauge.
The collected water is then measured with the help of measuring jar. The measuring jar reads in millimetres.
In areas of heavy rainfall, the reading of the rain is taken every three hours.
The gauge is kept on open ground on a 30cm flat-mount. Hence, the rainwater is collected without any obstruction.

Question 5
Fog, dew and frost
Answer:
(i) Fog:

The temperature of the layers of the air near the surface of the earth reduces. As temperature reduces, water vapour condenses.
In this process, vapour turns into microscopic water particles and float in the air.
When the density of these droplets in the air increases, fog occurs.

(ii) Dew:

When moisture-laden air near the earth’s surface comes in contact with very cold objects, condensation of the vapour takes place. They turn into very small water droplets.
These water droplets get stick to the surface of the cold objects. This is called dew.

(iii) Frost:

If the temperature of the air reaches less than 0°C, the water droplets stuck to the surfaces of cold objects and freeze.
This frozen water droplet is called frost.

Question 6.
Acid Rain
Answer:

Because of air pollution in industrial areas, various gases get mixed in the air.
Different adds are created when the water vapour in the air reacts chemically with these gases. For example, nitric add, sulphuric add, etc.
Acids dissolved in rainwater fall with the rain j during precipitation. Such a type of rain which has acids dissolved in it is called acid rain.
Such type of rainfall is harmful to the living organisms and the non-living objects.

Question 7.
Convectional Rainfall
Answer:

In equatorial areas, the surface gets heated because of the sun’s heat and the air near it also gets heated. As it gets heated, it spreads and becomes lighter and moves upwards.
It cools down when it goes upward & as the j moisture-holding capacity of cold air is less, condensation and rainfall occurs.
This type of rainfall is called as Convectional! Rainfall.
In equatorial areas, such a type of rainfall occurs almost daily in the afternoons. Rainfall is accompanied by lightning and thunder.
The Congo basin of the Africa and the Amazon basin in the South America experience convectional rainfall.
Such a rainfall has a very limited area on the earth.

Question 8.
Orographic rainfall
Answer:

Winds coming from lakes or seas are moisture-laden. They are obstructed by the high mountain ranges coming in their way.
They start going upwards along the slope of the mountains.
The temperature of these winds drop and condensation occurs and rainfall takes place. Thus because of the obstruction of the mountains, this type of rainfall occurs.
The windward side of the mountains gets; more rain; the amount of vapour in the air reduces after crossing the mountain and the moisture-holding capacity of the air increases.
The leeward side of the mountain gets lesser rainfall and hence this area is identified as rain- shadow area.

9th Std Geography Questions And Answers:

Std 9 Geography Chapter 10 Question Answer Maharashtra Board

February 4, 2025January 3, 2025 by Prasanna

Balbharti Maharashtra State Board Class 9 Geography Solutions Chapter 10 Urbanisation Human Notes, Textbook Exercise Important Questions and Answers.

Urbanisation Human Class 10 Questions And Answers Maharashtra Board

Class 9 Geography Chapter 10 Urbanisation Human Questions And Answers Maharashtra Board

Geography Class 9 Chapter 10 Question Answer Maharashtra Board

1. Suggest measures for the following problems:

(A) The slums in the cities are increasing.
Answer:

Creating more job opportunities in the rural areas so that migration is minimised.
Poverty alleviation schemes need to be implemented to improve the standard of living of the poor.
Initiative for improvement of sanitation, housing and other facilities must be facilitated.

(B) Because of the increasing traffic jams within the city, lot of time is consumed in commuting.
Answer:

To reduce traffic jams, carpooling is a great way to get to and fro work.
Planning the route in advance will help to avoid any road construction or other traffic jams.
Making use of public transportation like Railways, BEST, etc. will also help in reducing traffic congestion and precious fuel.

Many crimes are due to poverty and unemployment. Poverty alleviation and employment generation programmes should be given priority.
The semi-literate / educated unemployed persons should be given skill-training and be prepared for self-employment.
The police and the judicial system “should be strengthened to wipe out criminals.

(D) The problem of pollution is grave because of urbanisation.
Answer:

Walking or cycling to the work place will not only help in improving the health conditions of individuals but will also help in reducing pollution.
Cities need to green up (plant more trees) as trees are considered to be the natural purifiers.
Strict action should be taken against polluting industrial units.

(E) Migration has created questions of health and education in urban areas.
Answer:

Migration from rural to urban areas can be reduced if employment opportunities are provided in the rural areas.
Infrastructure like transport, electricity, public distribution system, etc. need to be provided in the rural areas.
Educational institutes and health centres need to be upgraded in the rural areas.

2. Match the correct pairs :

Group A – Group B
(1) Technological development and mechanization – (A) Urban areas
(2) Permanently staying away from your original place – (B) Lack of planning
(3) 75% males are engaged in non-agricultural occupation – (C) Migration
(4) The problems of solid waste – (D) Urbanisation
Answer:
(1-d),
(2- c),
(3 – a),
(4 – b)

3. Outline the importance/ advantages of the following:

(A) Technology and mechanisation
Answer:

Technology and mechanisation increase industrial production, creates employment and is useful for urbanisation.
In recent decades, the use of technology and mechanisation has increased in agriculture.
Due to the mechanisation of agriculture, the surplus manpower employed in agriculture have become devoid of agricultural work.
This working class started coming to cities to look for work and as a result urban population started increasing.

(B) Trade
Answer:

When a place in a region is favourable in terms of transport, loading-unloading and storage of goods, it developes into a trade centre.
This leads to the growth of business complexes, banks, credit societies, godowns, cold storage, houses, etc.
For example, Nagpur’s central location has facilitated trade and hence urbanisation has also taken place here.

Industrialisation leads to increase in the hopes of people who are attracted towards the industries from surrounding areas for employment.
Rapid growth of Mumbai in the 19th century was due to the textile mills which were started here.
Many fishing villages (Koliwadas) became part of Mumbai metropolitan2 area due to industrialisation and urbanisation.

(D) Amenities in urban areas
Answer:

Urbanisation leads to development of a number of amenities and facilities in urban areas.
Transportation, communication, educational facilities, medical facilities, fire brigade, various sources of entertainment, etc. are examples of amenities in urban areas.
A good transportation not only makes a journey easier but also has a positive effect on freight transport, development of markets, trade, etc.
Development of higher educational facilities in urban areas attract students from rural areas to urban areas. E.g. Pune.
Development of high quality medical facilities in urban areas bring many patients and their family members from different parts of India to these areas.

(E) Social harmony in the cities
Answer:

Social harmony refers to the exchange of cultural and social customs and traditions as people from different parts live together in the cities.
An increase in urbanisation leads to an increase in secondary, tertiary and quaternary occupation.
This results in an increase in employment opportunities due to which people from different parts of the country come to cities and there is an exchange of customs and traditions.

4. Compare the following and give examples:

(A) Transportation system and traffic jams
Answer:

As cities grow, people start living on the outskirts and in the suburbs of the city.
People commute to the centre of the city for businesses and industries, trade, jobs, education, etc.
Public transportation system is insufficient and hence the number of private vehicles increase.
This results in an increase in traffic jams and a lot of time is consumed in travelling from one place to another.
e.g. Although Mumbai has a well developed transportation system it is insufficient to fulfil the growing needs of people.

Hence, traffic jams are a frequent site in different pockets of Mumbai.

(B) Industrialisation and air pollution
Answer:

Industrialisation refers to the growth in number of industries in a particular region.
As more and more industries crop up, it becomes convenient for the industries to violate the environmental laws.
Paucity of facilities, insensitivity towards environment are the other factors which leads to an increase in the pollution level.
Hence, Industrialisation and Air pollution are the two aspects of the same coin.
e.g. Delhi, Faridabad and Varanasi are the ! victims of rapid industrialisation leading to j severe air pollution.

The increase in the number of migratory people causes an increase in the slums.
Generally migration from rural to urban areas takes place in search of job opportunities, which are hard to find.
The housing facilities do not increase in the same proportion as the population, so the poor migrants can not afford the housing in the cities.
This encourages the migrants to build illegal temporary and semi-structured houses known as slums, in open spaces. e.g. Slums in Dharavi (Mumbai city)

(D) Amenities and increasing crime
Answer:

Amenities refers to facilities that provide comfort, convenience or pleasure to people.
Transportation, communication, educational and medical facilities, fire brigade, etc. are the examples of amenities available in urban areas.
Unemployed people who have migrated to the cities are unable to avail these amenities.
This leads to an increase in thefts, burglaries, scuffles5, murders, etc. which disturb the social harmony of the cities.
e.g. Pick pocketing in the local trains.

5. Complete the table :

Process of urbanisation	Effects
Emergence of slums	Illegal settlements Insufficient facilities
	Increase in population because of attraction of good lifestyle Can be short-term or long-term
Pollution
	Employment opportunities were generated Increase in amenities and facilities
Change from rural to urban

Answer:

Process of urbanisation	Effects
Emergence of Slums	Illegal settlements Insufficient facilities
Migration	Increase in population because of the attraction of good lifestyle. Can be short-term or long term.
Pollution	Adverse effects on urban life.
Industrialisation	Employment opportunities have generated, increase in amenities and facilities.
Change from rural to urban	Formation of Municipal Corporation. better civic amenities, development of occupations.

6. Explain:

(A) The growth of cities takes place in a specific method.
Answer:
Villages are transforming into cities. The growth of cities take place in a particular pattern.

At first various industries like factories, mills, energy plants, multi-purpose projects3 etc., come up in rural areas.
People from surrounding areas come to work here and the population of the village increases.
To fulfill their needs other services develop like medical facilities, food, hospitals, recreation, etc.
The Gram Panchayat gives way to a Municipal Corporation.
These bodies provide basic services to citizens like drinking water, roads, transportation, sewerage network, street lighting etc.
Other facilities develop like town planning recreation facilities, tourist places, parks etc.

(B) A planned city of your imagination
Answer:

A city which is carefully planned from its inception and is constructed in a previously undeveloped area is a planned city.
A planned city is one in which there is adequate infrastructural facilities like roads, railways, water supply, power supply, etc.
Also, there should be open spaces available for recreation facilities.

The development and concentration of industries in a region is a factor contributing towards urbanisation.
Increase in industries leads to increase in the hopes of people who are attracted towards these industries from surrounding areas.
An increase in population leads to the development of infrastructural facilities like roadways, railways, power supply, water supply etc. which are the characteristics of a planned city.
In the 19th century, Mumbai grew rapidly because textile mills started on a large scale.

(D) Pollution- A problem
Answer:

Pollution is the introduction of contaminants into natural environment that causes adverse changes.
Pollution can be that of air, water, noise, solid waste, etc.
Pollution can adversely affect the human health.
Water pollution can lead to several water borne diseases like typhoid, cholera etc. Air pollution can lead to asthma and other respiratory diseases. Noise pollution can lead to sleep disturbance, hearing impairment etc.

(E) Swachchh Bharat Abhiyan
Answer:

Swatch Bharat Abhiyan is a cleanliness campaign run by the Government of India.
‘One step towards cleanliness’ is the objective of this campaign.
This campaign aims to keep the streets and infrastructure of the country’s cities, towns and its rural areas clean.
The funds for this programs are raised by ‘Swachchh Bharat Cess’.

7. Suggest measures for the following problems of urbanisation shown in the following pictures.

(1) Air Pollution:
Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 1
Answer:

Switching from coal, oil to natural gas as fuel in the industries.
Industrial areas should be located at a safe distance from residential areas.

(2) Noise Pollution:
Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 2
Answer:

Follow the limits of noise level.
Shut the door when using noisy machines.
To restrict noise pollution lower the volume of horns, loudspeakers, etc.

(3) Solid Waste Pollution:
Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 3
Answer:

Avoid disposing and littering of solid waste in the open.
Follow the principle of 4 R’s (Reduce, Recycle, Repair and Reuse) for non-biodegradable things.
Segregation of dry waste and wet waste for proper disposal.

(4) Water Pollution:
Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 4
Answer:

Sewage should not be allowed to mix with water sources without getting treated.
Avoid mixing industrial wastes and effluents directly into water sources.
Daily household chores should be avoided at water sources.

Class 9 Geography Chapter 10 Urbanisation Human Intext Questions and Answers

Can you tell?

Question 1.
Answer the following questions.

(i) Why is Suresh thinking of going to the factory for work?
Answer:

Suresh is thinking of going to the factory as it will get him a monthly salary.
Also, if he works overtime, he will get additional money and a bonus during Diwali.

Question 2.
What is Tatya worried about?
Answer:

Tatya is worried about the availability of labour in the agricultural field, since his son (Suresh) has decided to work in the factory.
Also, he is worried whether his son can manage working in the field and the factory simultaneously.

Question 3.
What changes does Suresh think will occur in the village?
Answer:

Development of goods and facilities like hospitals, schools and colleges, administrative offices, huge buildings are expected in the village.
The above factors will lead to migration of people from different villages which will bring about rural development.

Question 4.
What other changes do you think will occur in the village?
Answer:
There “will be well planned drainage systems, pure drinking water supply, street lightning, concrete roads, public library, etc. amenities will be provided. There will be fire station to control fires, police stations to control crimes. These changes are likely to occur in the village.

Give it a try.

Question 1.
Give example of villages in your area turning into urban settlement.
Answer:

Airoli, Nerul, Kopar Khairane, Vashi, Panvel, Taloja, Kamothe etc which comprises of Navi Mumbai (New Bombay) are the examples of villages turning into urban settlement.

Question 2.
Find out the main reason of that rural area turning into urban settlement.
Answer:
City and Industrial Development Corporation (CIDCO) planned and constructed all the railway stations, roads and public spaces in Navi Mumbai. APMC (Agricultural Produce Market Committee) which is a wholesale agricultural produce market at Vashi and Construction of Commuter railway line from Mankhurd to Vashi led to growth in economic activities and population in Navi Mumbai.

Question 3.
Obtain information regarding development of settlements, villages, towns, etc. located on the main transport routes in your surroundings in the last five years.
Answer:
In Mumbai along the Metro station route there are 2 settlements which have developed. They are Asalpha and Jagruti Nagar. Neither were very well-known places five years ago. But today they are important metro stations.

Question 4.
Make a list of cities in your district.
Answer:
I live in Thane District – Two of the cities are:

Bhiwandi
Badlapur.

Question 5.
Discuss which factors from above are responsible for their development.
Answer:
Factors responsible for development are:-

Bhiwandi – Industrialisation (Textile industry)
Badlapur – Transport (Connected to Mumbai – Pune expressway, has railway station on Mumbai – Pune route)

Question 6.
If possible, talk to people who have migrated in your surroundings or the nearest town and find out reasons of migration.
Answer:
People have migrated from Mumbai to Navi Mumbai.

The reasons are:

Better town planning
Better standard of living

Write five sentences on each picture after observing them.

Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 6
Answer:

In this picture the harmful gases, smoke released by the factory is causing air pollution.
Any substance that is introduced into the atmosphere and has damaging effects on living things and the environment is called Air Pollutant.
Air Pollution occurs when any harmful gases, dust, smoke enters into the atmosphere.
Air Pollution can lead to asthma, respiratory inflammation, decrease in living functioning and other respiratory diseases in humans.
The Ozone layer on the planet is depleting due to increased Air Pollution.

Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 7
Answer:

The picture shows heavy smog in a city causing air pollution.
Smog is a combination of smoke and fog.
Usually smog results from large amounts of coal burning in an area and is caused by a mixture of smoke and Sulphur dioxide.
It is a big problem in Beijing and New Delhi.
Smogs cause lung diseases.

Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 8
Answer:

In this picture we can see untreated polluted water being released into a river causing water pollution.
Water pollution is the contamination of water . bodies like lakes, rivers, oceans, etc.
Almost 80% of water pollution is caused by domestic sewage.
Water pollution can lead to several waterborne diseases like typhoid, cholera, dysentery, jaundice and malaria.
Water pollution affects marine life and the environment.

Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 9
Answer:

The picture shows a washerman washing clothes in a pond, thus polluting the water.
The soap and detergent used in bathing or washing contains certain chemicals which can pollute the water.
Water pollution affects the aquatic life.
Water pollution is a big menace to the economy, the environment and human health.
We should raise the awareness among the people about the causes and effects of water pollution.

Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 10
Answer:

In this picture we can see people are affected due to noise pollution caused by the loudspeakers.
Noise pollution is excessive noise that harms the balance of human or animal life.
Outdoor noise can be caused by machines, construction activities, vehicular traffic, sound of train or aircrafts, loudspeakers, etc.
Noise pollution can cause hypertension, high stress levels, hearing loss, sleep disturbances, etc.
Thus noise pollution affects both health and behaviour.

Observe the image and answer the following questions?

Maharashtra Board Class 9 Geography Solutions Chapter 10 Urbanisation Human 5

(i) What does the symbol signify?
Answer:
The symbol signifies an Indian Government campaign called ‘Swachh Bharat Abhiyan’, or ‘Clean India Movement’.

(ii) Obtain information regarding it through internet.
Answer:

Swachchh Bharat Abhiyan is a cleanliness campaign run by the Government of India.
The campaign involves the construction of latrines, promoting sanitation programmes in the rural areas, cleaning streets, roads and changing the infrastructure of the country to lead the country ahead.
It is launched as a responsibility of each and every citizen to make this country a Swachh country.
It was launched by Prime Minister Narendra Modi on the 145th birth anniversary of Mahatma Gandhi on 2nd October, 2014 at Rajghat, New Delhi.

(iii) Write how this programme is related to your daily life.
Answer:
In our daily life we see that in the rural and urban areas people are openly defecating, due to lack of latrines. This is not only an ugly sight, but also there are many adverse effects to it. There is a risk of contracting many diseases. Also it is unsafe for women and young girls.

Think about it.

Question 1.
Which facilities are necessary to be developed in urban areas for fulfilling the needs of the population?
Answer:
Facilities necessary to be developed in urban areas for fulfilling the needs of the population are:

Adequate water supply
Proper sewage system
Better means of transportation
Regular power supply
Sanitation
Health care centres
Schools and colleges.

Question 2.
Why do the sources of water near the city get polluted?
Answer:
The sources of water near the city gets polluted due to garbage from construction sites, and industrial areas, improper disposal of hazardous materials from garbage disposal companies, chemical spills and improper chemical disposal, sewage leaks, etc.

Question 3.
How is the polluted water disposed off in the cities?
Answer:
Almost 80% of the water pollution is caused by domestic sewage. This untreated sewage mixes with the various water bodies and causes water pollution.

Question 4.
Is the water supplied to the cities good for health?
Answer:

The cities have a chlorinated central water supply, managed by the government. But people living in illegal slums have been unable to legally connect to this system.
This forces many of them to illegally tap into city water pipes.
This has compromised the safety of the water supply through cross-contamination in many places.

Question 5.
What are the adverse effects of water, air and noise pollution on health?
Answer:
Pollution affects the health adversely. The effects are:

Water pollution can lead to several water borne diseases like typhoid, cholera, dysentery, jaundice and malaria.
Air pollution can lead to asthma, respiratory inflammation, lung functioning diseases and other respiratory diseases.
Noise pollution can lead to hearing impairment, hypertension, sleep disturbance and so on.

Use your brain power!

Write a paragraph suggesting measures of these problem of urbanisation.

Question 1.
When heaps of wastes accumulate bad odour and diseases are spread.
Answer:

To reduce the heaps of wastes reusable bags and containers must be used for shopping, travelling or packing lunches or leftovers.
Food scraps and garden waste can be combined to form compost.
Buy items made of recycled content and use and reuse them as much as you can.

Question 2.
Traffic jams are a regular routine.
Answer:

To reduce traffic jams, carpooling is a great way to get to and from work.
Planning the route in advance will help to avoid any traffic jams.
Making use of public transportation like railway, BEST etc will also help in reducing traffic congestion and precious fuel.

Find out.

Question 1.
Look for the changes that have occurred in the technology and mechanisation of agriculture with the help of internet. Write a short paragraph about the information you obtain.
Answer:
Mechanisation was one of the main factors responsible for urbanisation and industrialisation. Besides improving the production efficiency, mechanisation encourages large scale production and also improves the quality of production. On the other hand, mechanisation also displaces unskilled farm labour and causes environmental degradation (such as pollution, deforestation and soil erosion).

Try this.

Question 1.
Using the industrial information given in the table below, draw a line graph of the percentage of urban population. Discuss in terms of urbanisation. After studying this graph write the conclusion about urbanisation in our country from 1961-2011 in your own words.
Answer:
Observations:

The urban population has been increasing consistently from 1961 to 2011.
The growth of urban population was about 5.5 % from 1961 to 1981.
However, the growth of urban population was to 13.7% from 1981 to 2011.
Industrialisation, trade, mechanisation and technology, transport and communication and migration are factors responsible for increase in urban population.

Class 9 Geography Chapter 10 Urbanisation Human Additional Important Questions and Answers

Complete the statements choosing a colored option from the bracket:

Question 1.
In India is the main occupation.
(a) Industries
(b) Agriculture
(c) Banking
(d) Fishing
Answer:
(b) Agriculture

Question 2.
provides public service to the village.
(a) Gram Panchayat
(b) Municipal Council
(c) Government of India
(d) Army
Answer:
(a) Gram Panchayat

Question 3.
or provides public service to the urban areas.
(a) Municipal Council / Municipal Corporation
(b) Gram Panchayat / Gram sabha
(c) High Court / Supreme Court
(d) Government of India
Answer:
(a) Municipal Council or Municipal Corporation

Question 4.
Census of India decided to define ‘Urban’ in the year
(a) 1951
(b) 1961
(c) 1971
(d) 1981
Answer:
(b) 1961

Question 5.
For an urban area more than of the male working population must be engaged in non-agricultural occupation.
(a) 70%
(b) 75%
(c) 80%
(d) 85%
Answer:
(b) 75%

Question 6.
For an urban area, the population of the settlement should be more than
(a) 3000
(b) 4000
(c) 5000
(d) 6000
Answer:
(c) 5000

Question 7.
For an urban area, the density of population should be more than persons per sq.km.
(a) 400
(b) 300
(c) 500
(d) 700
Answer:
(a) 400

Question 8.
The growth of population from 1961 to 1981 was around
(a) 3.2%
(b) 4.3%
(c) 5.5%
(d) 6.5%
Answer:
(c) 5.5%

Question 9.
The growth of population from 1981 to 2011 was around
(a) 12.73%
(b) 14.73%
(c) 13.73%
(d) 12.83
Answer:
(c) 13.73%

Question 10.
The development and concentration of industries in a region is a factor contributing towards
(a) industrialisation
(b) mechanisation
(c) urbanisation
(d) agriculture
Answer:
(c) Urbanisation

Question 11.
In 19th century Mumbai grew rapidly because of
(a) shopping malls
(b) textile mills
(c) service industries
(d) agriculture
Answer:
(b) Textile mills

Question 12.
is a centrally located part of India.
(a) Nagpur
(b) Bhopal
(c) Bilaspur
(d) Pune
Answer:
(a) Nagpur

Question 13.
In the recent decades, the use of technology has increased in
(a) industries
(b) service
(c) agriculture
(d) engineering
Answer:
(c) agriculture

Question 14.
Manpower employed in agriculture become devoid of agriculture work due to
(a) industrialisation
(b) urbanisation
(c) mechanisation
(d) rains
Answer:
(c) Mechanisation

Question 15.
Convergence of important rail routes through led to its growth.
(a) Shirdi
(b) Pune
(c) Bhusaval
(d) Nagpur
Answer:
(c) Bhusaval

Question 16.
can be short-term, long term or permanent.
(a) Population growth
(b) Migration
(c) Trade
(d) Mechanisation
Answer:
(b) Migration

Question 17.
of a region changes largely due to urbanisation.
(a) Persona
(b) Geographical boundary
(c) Characteristics
(d) Trade
Answer:
(c) Characteristics

Question 18.
An increase in occupations leads to an increase in activities.
(a) non-economic
(b) agricultural
(c) economic
(d) social
Answer:
(c) economic

Question 19.
and social customs and traditions are exchanged as people from different parts live together in the cities.
(a) Political
(b) Economic
(c) Cultural
(d) Technological
Answer:
(c) Cultural

Question 20.
Exchange of culture, customs and traditions among people in the region creates
(a) oneness
(b) brotherhood
(c) social harmony’
(d) conflicts
Answer:
(c) social harmony

Question 21.
Due to, urban settlements get an advantage of new ideas, updated technologies and technological facilities.
(a) Jobs
(b) Modernisation
(c) Crime
(d) Migration
Answer:
(b) Modernisation

Question 22
Due to urbanisation, population iii the city increases rapidly but the do not increase in the same proportion.
(a) Entertainment facilities
(b) Sanitation facilities
(c) Housing facilities
(d) Irrigation facilities
Answer:
(c) housing facilities

Question 23.
give rise to social and health related issues.
(a) Scuffles2
(b) Thetis
(c) Slums
(d) Schools
Answer:
(c) Slums

Question 24.
is a major problem in the cities.
(a) Pollution
(b) Thetis
(c) Education
(d) Entertainment
Answer:
(a) Pollution

Question 25.
is a means to earn money through illegal ways.
(a) Harmony
(b) Crime
(c) Slum
(d) Industries
Answer:
(b) Crime

Match the following:

Column ‘A’	Column ‘B’
(1) Private vehicles due to insufficient public transportation.	(a) Crime
(2) Means to earn money through illegal ways.	(b) Pollution
(3) A major problem in the urban area that affects urban life.	(c) Slums
(4) Lack of basic facilities and narrow roads.	(d) Traffic jams

Answer:
(1 – d),
(2 – a),
(3 – b),
(4 – c)

Answer in one sentences:

Question 1.
What is urbanisation?
Answer:
Urbanisation is a process whereby population move from rural to urban area, enabling cities and towns to grow.

Question 2.
What should be the population density of a settlement, to be defined as an urban area?
Answer:
As per the Census of India (1961), the population density of the settlement should be more than 400 persons per sq.km.

Question 3.
Why did urbanisation start increasing in Nagpur?
Answer:
As Nagpur is centrally located in India, it faciliated trade and hence, urbanisation started increasing here.

Question 4.
What led to the rapid growth of village Savarde (District Ratnagiri)?
Answer:
Savarde’s proximity to the Konkan railway and conversion of important rail routes through Bhusawal (Dist. Jalgaon), led to the rapid growth of the village Savarde.

Question 5.
Which maj or factor has affected urbanisation?
Answer:
Migration is a major factor affecting urbanisation.

Question 6.
Name the types of migration based on time?
Answer:
The types of migration based on time are:

short-term migration
long-term migration and
permanent migration

Question 7.
Name the types of migration based on place?
Answer:
The types of migration based on place are:

rural to urban
urban to urban and
rural to rural

Question 8.
Which kind of occupations increase with urbanisation?
Answer:
There is an increase in secondary, tertiary and quaternary occupations with urbanisation.

Question 9.
How does urbanisation lead to social harmony?
Answer:
As people from different parts start living together in the cities, cultural and social customs as well as traditions are exchanged leading to social harmony.

Question 10.
Give any one reason why modernisation and urbanisation go together.
Answer:
In urban areas, people from different regions of the country migrate and exchange their wisdom, skills and knowledge resulting in modernisation.

Question 11.
Name some amenities and facilities that develop due to urbanisation.
Answer:
Transportation, communication, educational and medical facilities, fire brigade, etc. are some amenities and facilities that develop due to urbanisation.

Question 12.
Why do many students come to Pune city?
Answer:
Many students pursuing higher education come to Pune city, as it is well-known for these facilities.

Question 13.
Why do slums lack basic facilities?
Answer:
Most of the slums are illegal, so they do not get basic facilities from the local self governments.

Question 14.
What is the main reason for increase in the crime rate in the cities?
Answer:
The people who have migrated do not always find employment in the cities and hence crime rate has increased.

Question 15.
Which factors create tension in the cities?
Answer:
Increase in crime rates, enormous increase in land prices, struggle between various groups, etc. create tension in the cities.

Question 16.
Why do the sources of water near the city get polluted?
Answer:
Almost 80% of the water pollution is caused by domestic sewage. This untreated sewage mixes with the various water bodies and causes water pollution. Thus the sources of water near the city get polluted.

Question 17.
How is the polluted water disposed off in the cities?
Answer:
In the cities polluted water is treated in the waste water treatment plants before its disposal.

9th Std Geography Questions And Answers: