Class 8

Balbharti Maharashtra State Board Class 8 Geography Solutions Chapter 7 Population Notes, Textbook Exercise Important Questions and Answers.

Class 8 Geography Chapter 7 Population Questions And Answers Maharashtra Board

Population Class 8 Questions And Answers Chapter 7 Maharashtra Board

Class 8 Geography Chapter 7 Population Textbook Questions and Answers

1. Complete the following sentences:

Question A.
If the birth rate is greater than the death rate then the population …………. .
(i) decreases
(ii) increases
(iii) remains constant
(iv) becomes surplus
Answer:
(ii) increases

Question B.
People of …………… age group are included in the productive population.
(i) 0 to 14
(ii) 14 to 60
(iii) 15 to 60
(iv) 16 to 59
Answer:
(iv) 16 to 59

Question C.
The spread of modern technology in society is mostly dependent on …………….. .
(i) sex ratio
(ii) birth rate
(iii) literacy
(iv) migration
Answer:
(iv) migration

2. Examine the following statements and correct the incorrect ones:

Question a.
The population density of a region can be understood from its area.
Answer:
Incorrect.
Correct sentence: The population density of a region can be understood from its area and the total volume of population living in it.

Question b.
The quality of population is determined on the basis of literacy.
Answer:
Correct.

Question c.
There is an adverse impact on manpower in the regions of out migration.
Answer:
Correct.

Question d.
Greater economic prosperity indicates the development of region.
Answer:
Incorrect.
Correct sentence: Greater economic prosperity as well as higher standards of living, higher quality of life, availability of opportunities, freedom, etc, indicate the development of region.

Question e.
Developing countries have an HDl of 1.
Answer:
Incorrect.
Correct sentence: Developing countries have and HDI of 0.50 to 0.60.

3. Answer in brief.

Question a.
What are the aspects considered in the structure of population?
Answer:
The following are the aspects considered in the structure of the population:

1. Sex ratio/structure: Sex ratio/structure is a structure that considers the sub division of population on the basis of gender.
2. Age structure: Age structure is a structure that considers the sub division of population as per age groups.
3. Occupational structure: Occupational structure is a structure that considers sub division of population on the basis of dependency and workability.
4. Rural – urban structure: Rural – Urban structure is a structure that considers sub division of population on the basis of area of residence.
5. Literacy structure: Literacy structure is a structure that considers sub division of population on the basis of capability of reading and writing.

Question b.
Prepare a list of advantageous and disadvantageous factors, affecting population distribution.
Answer:
A list of advantageous factors affecting population distribution is as follows:

1. Availability of sufficient sunlight, clean air and water.
2. Region with low altitude
3. Moderate rainfall and temperature
4. Fertile soil
5. Deposits of minerals
6. Industrialisation
7. Urbanisation
8. Availability of transportation facilities
9. Availability of market
10. Political stability
11. International peace
12. Favourable government policies
13. Favourable social customs and traditions.

A list of disadvantageous factors affecting population distribution is as follows:

1. Shortage of sufficient sunlight, clean air and water.
2. Region with high altitude
3. Extremely less or more rainfall and temperature
4. Infertile soil
5. Scarcity of minerals
6. Low industrialisation
7. Lack of urbanisation
8. Non-availability of transportation facilities
9. Non-availability of market
10. Political instability
11. International disputes
12. Unfavourable government policies
13. Evil social customs and traditions.

Question c.
What are the problems in areas of high population densities?
Answer:
The ratio of the population of a country to its area is population density. While discussing population distribution, density of population is also considered. The density is calculated, as per the formula given below.
Density of population = Population of a region/Area of a region.

The problems in areas of high population densities are as follows:
1. Pollution – Pollution is one of the major reasons which people face due to high population density. Due to an increase in land degradation by making houses and flats, land pollution will be caused, water will be contaminated by a huge number of people, resulting in water pollution and huge number of vehicles will cause air pollution.

2. Overcrowded – The areas with high population density become overcrowded, which bring chaos and lack of peace in the society.
3. Lack of open space – High population density makes it difficult to get a free open space.

Question d.
What arc the problems in area of low population densities?
Answer:
The development of a country depends upon its size of population. A lower population is somehow manageable and resources can be distributed equally. But, sometimes the low population leads to lower demands of goods and services and lower tax revenues for the government to provide goods and services.

4. Give geographical reasons:

Question a.
Population is an important resource.
Answer:

1. The economic and cultural development of any country depends upon the volume and the quality of population.
2. If a country has a high volume and less quality of population, it has slow economic growth and development.
3. If a country has optimum population with high quality of population, it has fast economic growth and development. Thus, population is an important resource.

Question b.
Productive population is an important group.
Answer:

1. People belonging to age group of 16 to 59 age are considered as productive. Therefore this population is called productive population.
2. People below 16 years of age and above 60 years of age are considered as dependent or non-working population.
3. Productive population/people are involved in services or businesses. Therefore they play very important role in economic
4. If country has more proportion of productive population and youth, it develops rapidly. Thus, productive population is an important group.

Question c.
The study of age structure is important.
Answer:

1. The study of age structure helps to know the percentage of children, adolescents, youth, middle aged, and old aged in population.

2. The study of age structure helps to know the proportion of productive people (Working people between 16 years to 59 years of age) and unproductive people (Non working people below 16 years of age and above 60 years of age).

3. The study of age structure helps government in planning various economic, social, educational, medical, etc. schemes for the overall development of country.

4. The study of age structure helps to know the speed of economic growth. Thus, the study of age structure is important.

Question d.
Literacy is directly related to development.
Answer:

1. The country with high literacy rate, develops rapidly in economic, social and cultural aspects.
2. The country with low literacy rate, faces many obstacles in its economic, social and cultural growth and development.
3. Literacy rate is related to quality of life, the opportunities available and freedom. Thus, literacy is directly related to development.

Question e.
The real progress of a country is understood with the help of the Human Development Index.
Answer:
1. Human Development Index is calculated by taking into account the values of economic, health and education parameters.

2. Thus, Human Development Index is calculated on the basis of Gross National Product, life expectancy and literacy rate.

3. Human Development Index indicates the standard of living, economic and social welfare, quality of life, opportunities available and freedom. Therefore, the real progress of a country is understood with the help of the Human Development Index.

5. Write notes.

Question a.
Sex ratio.
Answer:
1. The number of females per thousand males is called sex ratio.

2. The sex ratio is calculated with the help of the following formula :

3. If the number of females per thousand males is less, the sex ratio is considered to be low. On the other hand, if the number of females per thousand males is more, the sex ratio is considered to be high.

4. According to Census 2011, the sex ratio was highest (1084) in the state of Kerala. According to Census 2011, the sex ratio was 929 in the state of Maharashtra.

5. Out-migration of males leads to high sex ratio in a region from where males have out-migrated. Less female birth rate leads to low sex ratio.

Question b.
Age structure.
Answer:

1. Sub division of population as per age groups is known as age structure.
2. Age structure is helpful in knowing the proportion of children, adolescents, young, middle aged and old people in population.
3. It is also helpful in knowing proportion of active population (Population between the ages 16 and 59) and dependent population (Population below 16 years of age and above 60 years of age).
4. Age structure is helpful to the government in framing various policies.

Question c.
Literacy.
Answer:
1. Population above the age of seven can be sub divided on the basis of capability of reading and writing.

2. People above the age of seven and are unable to read and write are considered illiterate. On the other hand, people above the age of seven and are able to read and write are considered literate.

3. High literacy rate is an indicator of social and economic development of society. On the other hand, high illiteracy rate leads to slow economic, social and cultural development of society.

4. Literacy rate is related to quality of life, the opportunities available and freedom. Thus, it is directly related to development.

Activity:

Question a.
Survey 5 families in your neighbourhood on the basis of the following points and make a presentation.
(a) Sex
(b) Age groups
(c) Education
(d) Occupation

Class 8 Geography Chapter 7 Population Additional Important Questions and Answers

Fill in the correct word and complete the sentences:

Question A.
……………… state of India has the highest sex ratio.
(i) Maharashtra
(i) Kerala
(c) Punjab
(d) Haryana
Answer:
(b) Kerala

Question B.
………………. district of Maharashtra has low density of population.
(a) Mumbai City
(b) Mumbai Suburb
(c) Thane
(d) Osmanabad
Answer:
(d) Osmanabad

Examine the following statements and correct the incorrect ones:

Question a.
The state of Maharashtra has a balanced population.
Answer:
Incorrect.
Correct sentence: The state of Maharashtra has imbalanced population.

Question b.
The areas with plenty of natural resources normally have more volume of population.
Answer:
Correct.

Question c.
The region with more proportion of youth in population has a rapid speed of development.
Answer:
Correct.

Question d.
Most of people in rural areas are engaged in tertiary activities.
Answer:
Incorrect.
Correct sentence: Most of people in rural areas are engaged in primary activities.

Question e.
Human Development Index is published by World Health Organisation.
Answer:
Incorrect.
Correct sentence: Human Development Index is published by United National Development Programme.

Question f.
Density of population is found to be more in the state of Goa.
Answer:
Correct.

Question g.
The state of Rajasthan is densely populated.
Answer:
Incorrect.
Correct sentence: The state of Rajasthan is sparsely populated.

Answer the following questions in one sentence each:

Question a.
What is birth rate?
Answer:
Birth rate is the number of live births per one thousand people in a year.

Question b.
What is death rate?
Answer:
Death rate is the number of deaths per one thousand people in a year.

Question c.
What is life expectancy?
Answer:
Life expectancy is the expected average life span of an individual at the time j of his/her birth.

Question d.
What is meant by in-migration?
Answer:
Migration of people in a particular region from outside regions is known as in-migration.

Question e.
What is meant by out-migration?
Answer:
Migration of people from a particular region to outside regions is known as out-migration.

Question f.
What is meant by sex ratio?
Answer:
The total number of females per thousand males is known as sex ratio.

Question g.
In which types of occupations are people in urban areas involved?
Answer:
People in urban areas are involved in secondary and tertiary occupations.

Question h.
Who put forth the concept of Human Development Index?
Answer:
Mahbub Ul Haq and Amartya Sen put forth the concept of Human Development Index.

Answer the following questions in brief:

Question a.
Explain the various types of migration.
Answer:
The various types of migration are as follows:

1. In-migration: In-migration is migration of people in a particular region from outside regions.
2. Out-migration: Out-migration is migration of people from a particular region to outside regions.
3. Short term mfgration: Short term migration is migration of people on a i temporary basis. For example, migration due to tourism or natural disaster or education is a short term migration.
4. Long term migration: Long term migration is migration of people on a permanent basis. For example, migration due to transfer of service or marriage or war j and partition is a long term migration.

Question b.
Explain the effects of migration.
Answer:
The effects of migration are as follows:

1. Out-migration leads to fall in population of a region from where people have migrated outside. This in turn leads to shortage of manpower in a region from where out-migration has occurred.

2. In-migration leads to increase in population of a region in which people from outside regions have migrated. This in turn, puts a pressure on public amenities and infrastructure of a region in which people have migrated.

3. Migration leads to redistribution of population.
4. Migration also leads to a change in the structure of population in a particular region.

Give geographical reasons:

Question a.
The density of population is found to be high in Mumbai City and Mumbai Suburb district.
Answer:

1. Mumbai is economic capital of India.
2. In Mumbai City and Mumbai Suburb district, industrialisation and urbanisation has taken place on a large scale.
3. Transportation, educational, medical, etc. facilities are available on a large scale in these districts.
4. Many employment opportunities are also available in these districts.

Due to all these favourable factors, many people from other districts of Maharashtra as well as from other states of India have migrated to Mumbai on a permanent basis. Therefore, the density of population is found to be high in Mumbai City and Mumbai Suburb district.

Study the following map/figure/graph and answer the following questions:

Study the Figure is given and answer the following questions:

Question a.
Which state has the highest sex\ratio?
Answer:
Kerala state has the highest sex j ratio.

Question b.
Which state has the lowest sex J ratio?
Answer:
Haryana state has the lowest sex ratio.

Question c.
What changes should take place in Maharashtra, to bring about a balanced > sex ratio and how much change is i necessary?
Answer:
The following changes should take place in Maharashtra to bring about a balanced sex ratio:

1. Sex ratio must get increased by having total control over female infanticide and launching various government schemes for women empowerment, etc.
2. The sex ratio must get increased by 71 i.e. the number of females per thousand males must get increased from 929 to 1000.

Try this: 

Question a.
Prepare bar graphs on the basis of the table given below and write a note. (Discuss in group about the issue of literacy in the country.)?

Answer:
(A) Bar graph:

(B) Note:

1. From the above bar diagram it can be seen that the literacy rate is found to be high in developed countries, moderate in developing countries and low in underdeveloped countries.
2. In 2010, the literacy rate was 72.1°/e in India.
3. In 2010, the literacy rate was 98.1% in Argentina and it was 38.1% in Afghanistan.
4. Literacy rate is directly or indirectly related to quality of life, opportunities available and the freedom.

Can you tell? 

Study Figure is given and answer the following questions:

Question a.
Which are the most densely populated districts?
Answer:
The most densely populated districts are:

1. Mumbai City
2. Mumbai Suburb
3. Thane
4. Pune
5. Kolha5ur, etc.

Question b.
Name the sparsely populated districts with a density of less than 100 per sq. km.
Answer:
The sparsely populated districts with a density of less than 100 sq. km:

1. Gadchiroli
2. Beed
3. Osmanabad, etc.

Question c.
Name two districts with moderate population.
Answer:
District with moderate population:

1. Nashik
2. Nagpur.

Question d.
What is the density of the dark shaded regions?
Answer:
The density of the dark shaded regions is greater than 1000 person per sq. km.

Question e.
Why is the density of population less in Gadchiroli?
Answer:
The density of population is less in Gadchiroli due to dense forests.

Question f.
Have a discussion in the class on the effect of physiography, climate, area under forest, industries, etc. on the density of population.
Answer:
1. Physiography: The density of population is found to be high in plain areas. On the other hand, the density of population is found to be low in mountainous regions.

2. Climate: The density of population is found to be high in the areas with moderate temperature and moderate rainfall. On the other hand, the density of population is found to be low in the areas of extremely low or high temperature and extremely high or low rainfall.

3. Area under forest: The density of population is found to be high in the area where forest cover is limited. On the other hand, the density of population is found to be low in the area under dense forests.

4. Industries: The density of population is found to be high in industrially developed region. The density of population is found to be low in industrially backward: region.

Thought-Provoking Questions:

Can you tell? 

Study the table is given and answer the following questions:

Question a.
Which city has greater number of newly born children?
Answer:
‘B’ City has greater number of newly born children.

Question b.
Which city records greater number of deaths?
Answer:
‘B’ City records greater number of deaths.

Question c.
Looking at the figures of in-migration and out-migration which city has received more migrants?
Answer:
Looking at the figures of in-migration and out-migration, ‘A’ City has received more migrants. .

Question d.
Calculate the population of both the cities in 2017.
Answer:
The population of ‘A’ City in 2017 is 121, 500 and of ‘B’ City in 2017 is 120, 550.

Question e.
After considering all the points, which city has recorded more growth of population in one year?
Answer:
After considering all the points, ‘A’ City has recorded more growth of population in one year. .

Question f.
The total number of births are given. What would be this figure per thousand population? What is the term for this?
Answer:
The total number of births are given. This figure would be 20 per thousand. The term for this is ‘Birth rate’.

Question g.
What would be the number of deaths per thousand population? What is the term used for this?
Answer:
The number of deaths per thousand would be 25. The term used for this is ‘Death rate’.

Complete the following table:
(Note: The answer is given directly.)

Question a.

Answer:

State	Population (2011)	Area (Sq. Km)	Density
1. Uttar Pradesh	19,98,12,341	2,40,926	829.35
2. Maharashtra	11,23,74,333	3,07,713	356.19
3. Tamil Nadu	7,26,26,809	1,30,058	558.41
4. Rajasthan	68,54,837	3,42,239	20.02
5. Manipur	27,21,756	22,327	121.90
6. Goa	14,58,545	3,702	393.98

Think about it:

Question a.
Even though area wise Rajasthan is a large state, the population is less. Which geographical factors may be responsible for this?
Answer:
The amount of rainfall is comparatively less in the state of Rajasthan. The Thar desert is located in the western part of the state of Rajasthan. Therefore, even though area wise Rajasthan is a large state, the population is less.

Can you tell? 

Question a.
Classify Male, Adolescent, Illiterate, Children, Unemployed, Infants, Literate, Rural, Working population, Urban, Female, Old, Young, Dependent population and Adult into the following categories:

1. Sex
2. Age
3. Rural
4. Urban
5. Literacy
6. Productive population.

Answer:

1. Sex: Male, Female
2. Age: Adolescent, Children, Infants, Old, Young, Adult
3. Rural: Rural
4. Urban: Urban
5. Literacy: Illiterate, Literate
6. Productive population: Unemployed, Working population, Dependent population.

Can you tell? 

Study the figure and answer the following questions:

Question a.
What do you think are the reasons for the changing land use pattern of Mondha village?
Answer:
Urbanisation and rise in population are the reasons for the changing land use pattern of Mondha village.

Question b.
What kind of changes have taken place?
Answer:
In Mondha village, the agricultural land use has decreased and the non-agricultural land use (i.e. commercial land use, residential land use) has increased.

Question c.
Due to this change in land use, do you think there has been a change in population? If yes, what is the change and why?
Answer:
Due to this change in land use, there has been a change in population. The population of Mondha has increased due to the in-migration.

Can you tell?

Study the table showing percentage of immigrant population of various countries given on page 46 and answer the following questions:

Question a.
Which countries have less than 10% migrant population?
Answer:
Afghanistan, Brazil, Bangladesh, India and Great Britain have less than 10% migrant population.

Question b.
Which are the countries with a migrant population of between 10% and 20%?
Answer:
Germany and U.S.A. are the countries with a migrant population of between 10%
and 20%.

Question c.
Which are the countries with a migrant population of more than 20%
Answer:
Kuwait, Hong Kong, Oman and Saudi Arabia are the countries with a migrant population of more than 20%.

Question d.
Find the reasons behind the migrant population of more than 20%.
Answer:
The reasons behind the migrant population of more than 20% are:

1. Huge stock of mineral oil and other natural resources
2. Availability of employment opportunities
3. Great demand for labour in these countries.

Question c.
Draw pie diagrams for any two countries.
Answer:
1. Kuwait: A pie diagram showing percentage of immigrant population for Kuwait is as follows:

2. Oman: A pie diagram showing percentage of immigrant population for Oman is as follows:

Question d.
Have a discussion on migration and development.
Answer:
1. Out-migration leads to a shortage of manpower/labour supply. This in turn adversely affects the development of the region from where out-migration has occurred.
2. In-migration leads to increase in population of a region in which in-migration has occurred. This too, adversely affects the development of the respective region.
3. The migration up to certain extent increases the mobility of labourer and it boosts the development of a particular region.

Use your brainpower: 

Question a.
In India, 0.52 % of the population are migrants. What is the actual number of people who have migrated to India?
Answer:
According to Census 2011, the population of India was nearly 121 crore. In India, 0. 52 % of the population are migrants. Thus, according to Census 2011, the actual number of people who have migrated to India is nearly 629,200.

Try this:

Question a.
Write a note on the Human Development Index. (HDI) of various countries on the basis of the following table:
HDI Rank wise Country Value of HDI Level of Development

Answer:

1. Norway ranks first in the world with respect to Human Development Index (HDI). The value of HDI for Norway is 0.949.
2. The countries like Japan, United Kingdom, Denmark, Switzerland, Germany and Australia have the value of Human Development Index (HDI) more than 0.900. These countries show very high level of development.
3. The countries like Sri Lanka, Brazil and China have the value of Human Development Index (HDI) between 0.700 and 0.800. These countries show high level of development.
4. The countries like India, Bhutan and Pakistan have the value of Human Development Index (HDI) between 0.500 and 0.600. These countries show medium level of development.
5.  The countries like Niger and Central African Republic have value of Human Development Index (HDI) between 0.300 and 0.400. These countries show less development.
6. From the above table it can be seen that Human Development Index (HDI) is an indicator of development.
7. Higher value (around 1) of Human Development Index indicates high level of development and lower value (around 0) of Human Development Index indicates low level of development.

Use your brain power:

Question a.
Discuss and write the advantages and disadvantages of low population or high population with reference to the following factors:
(Note: The answer is given directly.)

Answer:

Headings	Low population	High population
Per capita land availability	Per capita land availability is comparatively more.	Per capita land availability is comparatively less.
Foodgrains	Food grains are available in plenty.	There is shortage of food grains.
Resources	Resources are available in plenty.	There is strain on resources.
Per capita income	Per capita income is comparatively high.	Per capita income is comparatively low.
Basic amenities and facilities	Basic amenities and facilities are available in sufficient quantity.	There is strain on basic amenities and facilities.
Percentage of unproductive consumers	Percentage of unproductive consumers is comparatively low.	Percentage of unproductive consumers is comparatively high.
Planning	Planning is comparatively more effective.	Planning is comparatively less effective.
Employment	More employment opportunities are available.	Less employment opportunities are available.
Urbanisation	The rate of urbanisation may be comparatively low.	The rate of urbanisation may be comparatively high.
Health	The quality of health may be comparatively high.	The quality of health may be comparatively low.
Higher education	The number of highly qualified people may be comparatively more.	The number of highly qualified people may be comparatively low.
Social environment	Social environment may be comparatively supportive and favourable.	Social environment may be comparatively adverse and unfavourable.

Give it a try:

Question a.
Since the past two centuries, the size of family is decreasing. But inspite of this the population of the country is increasing. Find out why is this happening.
Answer:
1. Since the past two centuries, the death rate in India has reduced to a great extent. On the other hand, since the past two centuries, the birth rate in India has reduced negligibly. Therefore, since the past two centuries, the size of family is decreasing. But in spite of this the population of country is increasing.

Use your brain power:

Question a.
As per the population Census of 2011, the population of India is 121 crores. For domestic use, the per capita requirement per day is 50 litres of water. Taking this into account, what would be the total amount of water requirement in India for domestic purpose only.
Answer:

1. As per the Population Census of 2011, the population of India is. 121 crores?
2. For domestic use, the per capita requirement per day is 50 litres of water.
3. Taking this into account, the total amount of water requirement in India for domestic purpose only, will be nearly 6050 crores litre.

Open-Ended Questions:

Question a.
What are the problems in areas of high population distribution?
Answer:
The following are the problems in areas of high population distribution:

1. Increased level of water, air, sound and soil pollution.
2. Traffic jam
3. Shortage of residential areas
4. Increased criminal tendencies, etc.

Question b.
What are the problems in areas of low population densities?
Answer:
The following are the problems in areas of low population densities:

1. Shortage of labour supply
2. Low levels of demand for various goods and services
3. Under utilization of resources, etc.

Give it a try:

Question a.
How do imbalanced sex ratios affect the society?
Answer:
Imbalanced sex ratios affect the society as follows:

1. Increased problems in society, workplace, etc.
2. Increased crimes against women.

Question b.
What measures can be taken to strike a balance in the sex ratio?
Answer:
The following measures can be taken to strike a balance in the sex ratio:

1. Increasing literacy rate of females.
2. Increasing employment opportunities for women.
3. Eradicating evil social customs.
4. Launching government schemes of women empowerment.

8th Std Geography Questions And Answers:

• Local Time and Standard Time Class 8 Geography Questions And Answers
• Interior of the Earth Class 8 Geography Questions And Answers
• Humidity and Clouds Class 8 Geography Questions And Answers
• Structure of Ocean Floor Class 8 Geography Questions And Answers
• Ocean Currents Class 8 Geography Questions And Answers
• Land Use Class 8 Geography Questions And Answers
• Population Class 8 Geography Questions And Answers
• Industries Class 8 Geography Questions And Answers
• Map Scale Class 8 Geography Questions And Answers
• Field Visit Class 8 Geography Questions And Answers

Balbharti Maharashtra State Board Class 8 Geography Solutions Chapter 5 Ocean Currents Notes, Textbook Exercise Important Questions and Answers.

Class 8 Geography Chapter 5 Ocean Currents Questions And Answers Maharashtra Board

Ocean Currents Class 8 Questions And Answers Chapter 5 Maharashtra Board

Class 8 Geography Chapter 5 Ocean Currents Textbook Questions and Answers

1. Choose the correct option:

Question a.
In which ocean does the Labrador current flow?
(a) Pacific
(b) South Atlantic
(c) North Atlantic
(d) Indian
Answer:
(c) North Atlantic

Question b.
Which current out of the following flows in the Indian Ocean?
(a) East Australian current
(b) Peru current
(c) South Polar current
(d) Somali current
Answer:
(d) Somali current

Question c.
Which factor out of the following does not affect the region along the coast?
(a) Precipitation
(b) Temperature
(c) Land breeze
(d) Salinity
Answer:
(c) Land breeze

Question d.
Which of the following occurs in the area where the cold and warm currents meet?
(a) High temperature
(b) Snow
(c) Low temperature
(d) Thick fog
Answer:
(d) Thick fog

Question e.
Which of these following currents flow from the northern polar regiorTup to Antarctica?
(a) Warm ocean currents
(b) Surface ocean currents
(c) Cold ocean currents
(d) Deep ocean currents
Answer:
(d) Deep ocean currents

2. Examine the given statements and correct the wrong ones:

Question a.
Ocean currents give specific direction and velocity to the water.
Answer:
Correct.

Question b.
The deep ocean currents flow with high velocity.
Answer:
Correct.

Question c.
Generally, surface ocean currents are formed in the equatorial regions.
Answer:
Incorrect.
Correct statement: Generally, surface ocean currents are formed in the equatorial region as well as polar region.

Question d.
Ocean currents hold great importance for human life.
Answer:
Correct.

Question e.
The movement of icebergs is not dangerous for water transport.
Answer:
Incorrect.
Correct statement: The movement of icebergs is dangerous for water transport.

Question f.
Water becomes warm near Brazil due to ocean currents. On the other hand, it becomes cold near African coast.
Answer:
Incorrect.
Correct statement: Water becomes warm near Brazil due to ocean currents. Similarly, it also becomes warm near African coast.

3. Explain the effect of-

Question a.
Warm ocean currents on climate.
Answer:

1. The amount of precipitation increases in the coastal region along with which the warm ocean currents flow.
2. Similarly, the temperature increases in the coastal region along with which the warm ocean currents flow.

Question b.
Cold ocean currents on the movement of icebergs.
Answer:

1. Due to cold ocean currents, icebergs are moved away from the polar regions.
2. These icebergs come along the marine routes and prove hazardous to the ships.

Question c.
The shape of the coastline on ocean currents.
Answer:

1. The extended parts of coastline acts as an obstacle for ocean currents.
2. The extended parts of coastline alters the direction and velocity of ocean currents.

Question d.
Meeting of warm and cold ocean currents.
Answer:

1. Dense fog is found in the meeting point of warm and cold ocean currents. Algae, plankton, etc. fish food grow on a large scale in these areas.
2. Fish come in these areas on a large scale and breed. Therefore, extensive fishing grounds are found in the areas where warm and cold ocean currents meet.

Question e.
The transportation capacity of ocean currents.
Answer:

1. The transportation capacity of ocean currents alters the amount of precipitation and temperature in the coastal regions along with which they flow.
2. The transportation capacity of ocean currents leads to transfer of warm water to the bottom from the surface and cold water to the surface from the bottom.

Question f.
Deep ocean currents.
Answer:

1. Deep ocean currents leads to transfer of warm water to the bottom from the surface and cold water to the surface from the bottom.
2. Deep ocean currents thus leads to redistribution of sea water.

4. Look at the map of ocean currents and answer the following:

Question a.
How does the Humboldt current affect the climate of the South America?
Answer:
Humboldt current is a cold ocean current and so it decreases the amount of precipitation and temperature on the western coastal region of the South America.

Question b.
In which oceans are counter equatorial currents not observed and why?
Answer:
Counter equatorial currents are not observed in Arctic Ocean and Southern Ocean. These oceans are located near the polar regions. Therefore, the effects of trade winds is found to be less in these oceans Therefore, counter equatorial currents are not observed in these oceans.

Question c.
Which currents are absent in the northern part of the Indian Ocean and why?
Answer:
Cold currents are absent in the northern part of the Indian Ocean. The northern part of Indian Ocean is included in the temperate zone. So cold currents are absent in the northern part of the Indian Ocean.

Question d.
In which regions do the cold and warm ocean currents meet?
Answer:
The cold and warm ocean currents S meet in the following regions:

1. North Atlantic Ocean (cold Labrador current and warm Gulf stream current)
2. North Pacific Ocean (cold Oyashio current and warm ! Kurishio current)
3. South Atlantic Ocean ! (cold Falkland current and warm Brazil current)
4. South Pacific Ocean (cold South Polar current and warm East Australian current)
5. Indian Ocean (cold South Polar i current and Agulhas Current)

5. Answer the following questions:

Question a.
What are the reasons responsible for the formation of deep ocean currents?
Answer:

1. The temperature varies in various parts of ocean.
2. Similarly, the density of water in various parts of ocean is also found to be different.
3. The difference in the temperature and density of seawater leads to its circulation and the deep ocean currents are formed. This circulation is known as thermohaline circulation.

Thus, the difference in temperature and density of water in various parts of ocean are the reasons responsible for the formation of deep ocean currents.

Question b.
What is the reason behind the dynamics of the ocean water?
Answer:
Planetary winds is the reason behind the dynamics of the ocean water.

Question c.
How do winds give direction to the ocean currents?
Answer:
Winds give clockwise direction to the ocean currents in the northern hemisphere and anti-clockwise direction to the ocean currents in the southern hemisphere.

Question d.
Why do the ports in the eastern coast of Canada freeze in winter?
Answer:

1. Labrador cold current flows along the eastern coast of Canada.
2. Due to Labrador cold current, the temperature of sea water near the eastern coast of Canada decreases.
3. Due to fall in temperature, the sea water along the eastern coast of Canada start freezing. As its effect, the ports in the eastern coast of Canada freeze in winter.

Activity:

Question a.
Look for more funny and interesting information related to ocean currents.

Class 8 Geography Chapter 5 Ocean Currents Additional Important Questions and Answers

Examine the following statements and correct the incorrect ones:

Question a.
Labrador is a warm ocean current.
Answer:
Incorrect.
Correct statement: Labrador is a cold ocean current.

Question b.
Surface ocean currents flow with high velocity.
Answer:
Incorrect.
Correct statement: Surface ocean currents flow with slow velocity.

Question c.
Even though the velocity of ocean currents is less, the water carried by them is immense.
Answer:
Correct.

Question d.
The ocean currents flow near the lower boundary of the continental shelf.
Answer:
Correct.

Answer the following questions in one sentence each:

Question a.
What are the main types of ocean currents?
Answer:
Cold ocean currents and warm ocean currents are the main types of ocean currents.

Question b.
In which region are the warm ocean currents formed?
Answer:
The warm ocean currents are formed in the equatorial region.

Question c.
In which regions are the cold ocean currents formed?
Answer:
The cold ocean currents are formed in the polar regions.

Question d.
Which factors are responsible for the formation of ocean currents?
Answer:
Difference in temperature of seawater, difference in density of seawater and planetary winds are the factors responsible for the formation of ocean currents.

Question e.
Which factors are responsible for the direction of flow and velocity of ocean currents?
Answer:
Rotation of the earth and continental structure are the factors responsible for the direction of flow and velocity of ocean currents.

Question f.
In which unit is the discharge of water in the oceans measured?
Answer:
The discharge of water in the oceans is measured in the Sverdrup unit.

Question g.
What is meant by 1 Sverdrup discharge?
Answer:
1 Sverdrup discharge means 1 million cu.m./second discharge of ocean water.

Question h.
Which two ocean currents meet near Newfoundland Island?
Answer:
Gulf warm ocean current and Labrador cold ocean current meet near Newfoundland Island.

Match the columns and complete the chain:

Question a.

‘A’ Column	‘B’ Column	‘C’ Column
1. California Current	i. South Atlantic Ocean	a. Near the eastern coast of the continent of North America
2. Hamboldt Current	ii. North Pacific Ocean	b. Near the eastern coast of the continent of South America
3. Brazil Current	iii. North Atlantic Ocean	c. Near the western coast of the continent of South America
4. Gulf Current	iv. South Pacific Ocean	d. Near the western coast of the continent of North America

Answer:

‘A’ Column	‘B’ Column	‘C’ Column
1. California Current	ii. North Pacific Ocean	d. Near the western coast of the continent of North America
2. Hamboldt Current	iv. South Pacific Ocean	c. Near the western coast of the continent of South America
3. Brazil Current	i. South Atlantic Ocean	b. Near the eastern coast of the continent of South America
4. Gulf Current	iii. North Atlantic Ocean	a. Near the eastern coast of the continent of North America

Answer the following questions in brief:

Question a.
Write in brief about warm ocean currents.
Answer:
1. Ocean currents that move water away from the Equator to the poles are called warm ocean currents.
2. Warm ocean currents are formed in the equatorial region and they flow towards the poles.

3. The warm currents increase the temperature and precipitation in the coastal areas along with which they flow. For example, the warm ocean currents flowing along with the coastal areas of Western Europe, Southern Alaska and Japan increases the temperature in the coastal areas along with which they flow. As its effect, the ports in the coastal areas of Western Europe, Southern Alaska and Japan do not freeze in winter.

4. Gulf stream, Agulhas, Somali, etc. are some of the warm ocean currents.

Question b.
Write in brief about cold ocean currents.
Answer:
1. Ocean currents that move water away from the poles to the Equator are called cold ocean currents.
2. Cold ocean currents are formed in the polar region and they flow towards the equatorial region.

3. The cold currents decrease the temperature and precipitation in the coastal areas along with which they flow. For example, the cold ocean currents flowing along with the coastal areas of Peru, Chile, and southeastern Africa, decreases the amount of precipitation in the coastal areas along with which they flow. As its effect, arid desert areas are formed in Peru, Chile, and southwestern Africa.

4. Falkland, Labrador, Canary, Oyashio, Benguela, etc. are some of the cold ocean currents.

Question c.
Write in brief about conveyor belt.
Answer:

1. Due to deep ocean currents, the warm water goes down and the cold water comes to the surface of the earth.
2. Thus, deep ocean currents redistribute the ocean water.
3. This redistribution of ocean water takes around 500 years to complete.
4. This redistribution (movement) of sea water is known as conveyor belt.

Question d.
Write in brief about relation between ocean currents and fishing.
Answer:

1. Algae, plankton, etc. fish food grow on a large scale in the areas where warm ocean current and cold ocean current meet.
2. Fish come in these areas on a large scale and breed. Therefore, extensive fishing
   grounds are found in the meeting point of warm and cold ocean currents.
3. For example, Grand Bank in Atlantic Ocean near the coastal region of North America, Dogger Bank near the continent of Europe, etc.

Explain the effect of the following:

Question a.
Cold ocean currents on climate.
Answer:

1. The amount of precipitation decreases in the coastal region along with which the cold ocean currents flow.
2. Similarly, the temperature decreases in the coastal region along with which the cold ocean currents flow.

Give geographical reasons:

Question a.
Fog is found near Newfoundland island.
Answer:

1. Fog is found at the meeting point of warm and cold ocean currents.
2. Warm Gulf Stream ocean current and cold Labrador ocean current meet near Newfoundland island. Therefore, fog is found near Newfoundland island.

Question b.
Ocean transport is carried out along with ocean currents.
Answer:

1. Ocean transport carried out along with ocean currents increases the speed of ocean transport and so saves the time.
2. Ocean transport carried out along with ocean currents decreases the cost of fuel. Therefore, ocean transport is carried out along with ocean currents.

Question c.
Extensive fishing ground is found near Newfoundland island.
Answer:

1. Warm Gulf Stream ocean current and cold Labrador ocean current meet near Newfoundland island.
2. Algae, plankton, etc. fish food grow on a large scale in the meeting point of warm Gulf Stream ocean current and cold Labrador ocean current.
3. Fish come in this area on a large scale and breed. Therefore, extensive fishing ground is found near Newfoundland island.

Differentiate between the following:

Question a.
Cold ocean current and Warm ocean current:
Answer:

Question b.
Surface ocean current and Deep ocean current:
Answer:

Study the following map/figure /graph and answer the following questions:

Make friends with maps!

Study the Figure and answer the following questions:

Question a.
What are the major types of ocean currents?
Answer:
Warm ocean currents and cold ocean currents are the major types of ocean currents.

Question b.
What do you call the currents flowing from the equator to the poles?
Answer:
The currents flowing from the equator to the poles are called warm currents.

Question c.
What do you call the currents flowing from the poles to the equator?
Answer:
The currents flowing from the poles to the equator are called cold currents.

Question d.
When the currents are moving in a circular manner, what difference is visible in their direction in Northern and Southern Hemisphere respectively?
Answer:
When the currents are moving in a circular manner, they will move in clockwise in Northern Hemisphere and anti-clockwise in the Southern Hemisphere.

Question e.
What might happen at the places where these two currents meet?
Answer:
Dense fog will get formed at the places where these two currents meet.

Question f.
When two different types of currents meet along the coast then what type of human settlements and occupations are seen?
Answer:
When two different types of currents meet along the coast then dense human settlements and fishing occupation are seen there.

Make friends with maps!

Question a.
Where did a container full of toys fall on 10th January, 1992?
Answer:
A container full of toys fell near the Hawaii Island on 10th January, 1992.

Question b.
Where did some of the toys reach on 16th November, 1992?
Answer:
Some of the toys reached the coast of Alaska on 16th November, 1992.

Question c.
Where did some of the toys reach by the year 2000?
Answer:
Some of the toys crossed the Bering Strait and reached the Arctic Ocean by the year 2000.

Question d.
Where did some of the toys reach by the year 2003?
Answer:
Some of the toys reached the eastern coast of America by the year 2003.

Question e.
Where did some of the toys reach by the year 2007?
Answer:
Some of the toys reached the western coast of continent of Europe by the year 2007.

Question f.
Why did the toys travel in this way?
Answer:
The toys travelled in this way due to surface ocean currents and mostly due to deep ocean currents.

Thought Provoking Question:

Question a.
What will be the effect of Westerlies on the ocean currents?
Answer:

1. Due to the influence of the Westerlies, the ocean currents will flow from west to east in the mid-latitudes.
2. Due to the influence of Westerlies, the ocean currents will flow from east to west in equatorial region. This in turn, will lead to a circular pattern of sea currents.

Open-Ended Question:

Question a.
With which points will you explain the effects of ocean currents?
Answer:
The effects of ocean currents can be explained with the help of the following points:

1. Temperature: Ocean currents brings change in the temperature of the coastal areas along with which they flow. For example, the warm ocean current flowing along the coastal areas of Japan increases the temperature in the coastal areas.

2. Precipitation: Ocean currents brings change in amount of precipitation in the coastal areas along with which they flow. For example, the cold ocean current flowing along the coastal areas of Chile decreases the precipitation in the coastal areas leading to formation of desert areas.

3. Occupation: Ocean currents also supports the growth of fishing occupation. The extensive fishing grounds redeveloped the meeting point of warm and cold ocean currents. For example, Grand Bank near the continent of North America.

4. Transportation: Sea transport carried out along with ocean currents increases the speed and reduces the cost of fuel.

8th Std Geography Questions And Answers:

• Local Time and Standard Time Class 8 Geography Questions And Answers
• Interior of the Earth Class 8 Geography Questions And Answers
• Humidity and Clouds Class 8 Geography Questions And Answers
• Structure of Ocean Floor Class 8 Geography Questions And Answers
• Ocean Currents Class 8 Geography Questions And Answers
• Land Use Class 8 Geography Questions And Answers
• Population Class 8 Geography Questions And Answers
• Industries Class 8 Geography Questions And Answers
• Map Scale Class 8 Geography Questions And Answers
• Field Visit Class 8 Geography Questions And Answers

Balbharti Maharashtra State Board Class 8 Geography Solutions Chapter 2 Interior of the Earth Notes, Textbook Exercise Important Questions and Answers.

Class 8 Geography Chapter 2 Interior of the Earth Questions And Answers Maharashtra Board

Interior of the Earth Class 8 Questions And Answers Chapter 2 Maharashtra Board

Class 8 Geography Chapter 2 Interior of the Earth Textbook Questions and Answers

1. Tick [✓] the correct options in the box:

Question A.
There are two layers in the crust.
(a) Inner and outer crust [ ]
(b) Continental and oceanic crust [ ]
(c) Surface and oceanic crust [ ]
(d) Mantle and core [ ]
Answer:
(b) Continental and oceanic crust [✓]

Question B.
Which element is found in both mantle and crust?
(a) Silica [ ]
(b) Magnesium [ ]
(c) Aluminium [ ]
(d) Iron [ ]
Answer:
(b) Magnesium [✓]

Question C.
Which of these minerals are found in the core of the earth?
(a) Iron – magnesium [ ]
(b) Magnesium – nickel [ ]
(c) Aluminium – iron [ ]
(d) Iron – nickel [ ]
Answer:
(d) Iron – nickel [✓]

Question D.
The inner core is in which state?
(a) Gaseous [ ]
(b) Solid [ ]
(c) Liquid [ ]
(d) Semi-solid [ ]
Answer:
(a) Gaseous [✓]

Question E.
The outer core is made up of
(a) Iron [ ]
(b) Gold [ ]
(c) Hydrogen [ ]
(d) Oxygen [ ]
Answer:
(a) Iron [✓]

Question F.
The layer of the earth on which we live…
(a) Mantle [ ]
(b) Core [ ]
(c) Crust [ ]
(d) Continental crust [ ]
Answer:
(d) Continental crust [✓]

2. Tell whether right or wrong. Correct the wrong statement

Question A.
The density of various materials is not the same in the interior of the earth.
Answer:
Correct.

Question B.
The core of the earth’s interior is made up of hard rocks.
Answer:
Incorrect.
Correct statement: The core of the earth’s interior is made up of elements, viz. iron and nickel.

Question C.
Secondary waves cannot pass through outer core.
Answer:
Correct.

Question D.
Continental crust is made up of silica and magnesium.
Answer:
Incorrect.
Correct statement: Continental crust is made up of silica and aluminum.

3. Answer the following

Question A.
What are the two parts of the crust? What is the basis of classification?
Answer:

1. Continental crust and the Oceanic crust are the two parts of the crust.
2. The crust is classified on the basis of whether it lies below the land or the ocean.
3. The part of the crust lying below the continent is known as the continental crust.
4. The part of the crust lying below the ocean is known as the oceanic crust.

Question B.
Why is the upper layer of the mantle known as the asthenosphere?
Answer:

1. The upper layer of the mantle is in liquid state.
2. The rocks in the upper 100 to 200 km of the mantle melt due to the heat and magma is created. Magma chambers are found in this layer of the earth.
3. Due to the heat and pressure, the energy waves are created in mantle. These energy waves move in vertical direction and magma comes out on the surface of the earth by volcanic eruptions.
4. These endogenitic movements continuously occur in the upper layer of the mantle. Therefore, the upper layer of the mantle is known as the asthenosphere.

Question C.
Magnetosphere of the earth is a result of rotation. Explain.
Answer:
1. The average temperature of the outer core of the earth is around 5000° C. The average temperature of the inner core of the earth is around 6000° C. This difference between the temperature results in formation of vertical currents.

2. The rotation of the earth gives eddy (circular) motion to these currents.

3. Electric currents develop in these spiral eddies of liquid iron leading to generation of the magnetic field of the earth. This magnetic field is called magnetosphere. In this way, the magnetosphere is formed due to the rotation of the earth.

4 Draw neat diagrams. label them and explain.

Question A.
The interior of the earth
Answer:

Explanation:

1. Inner Core: It is the center and the hottest layer of the Earth. The inner core is solid and made up of iron and nickel.
2. Outer Core: The outer core of the Earth is similar to a very hot ball of metals. It is composed of metals such as iron and nickel. The outer core surrounds the inner core.
3. Mantle: Mantle is the widest section of the Earth. Mantle is mainly made up of semi-molten rock known as magma. The rock is hard in the upper part of the mantle, but lower down the rock is softer and begins to melt. The mantle consists of very hot and dense rock.
4. Crust: The crust is the outer layer where we live. It’s a solid rock layer divided into two types: Continental crust covers the land and Oceanic crust covers water.

Question B.
Magnetic pole and equator
Answer:

5. Give geographical reasons:

Question A.
There are discontinuities in the interior of the earth.
Answer:
1. There is a difference between the elements, temperatures and the pressure found in the three parts of the interior of the earth, viz, crust, mantle and core.

2. In the interiors of the earth, the transitional areas are found between (a) continental crust and oceanic crust (b) crust and mantle (c) upper mantle and lower mantle (d) mantle and core and (e) outer core and inner core. Therefore, there are discontinuities in the interior of the earth.

Question B.
There is correlation between the density of metals and their location in the interior of the earth.
Answer:
1. The rocks found in the crust have predominance of the compounds of silicon, aluminium, magnesium, etc. These compounds are lighter in weight. Therefore, they are found in the upper layer of the interior of the earth.

2. The elements like iron, nickel are found in the core of the earth. These elements are heavier in weight. Thus, metals with low density are found in upper level in the interior of the earth and the metals with high density are found in the lower level in the interior of the earth. Thus, there is correlation between the density of metals and their location in the interior of the earth.

Question C.
Mantle is the centre of earthquake and volcanic eruptions.
Answer:
1. The rocks in the upper 100 to 200 km of the mantle melt due to the heat and the magma is created.
2. Magma chambers are found in this layer of the earth.

3. Due to the heat and pressure, the energy waves are created in mantle. These energy waves move in vertical direction and magma comes out on the surface of the earth by volcanic eruptions. Thus, mantle is the centre of earthquake and volcanic eruptions.

Question D.
The thickness of the crust below the continents is more as compared to oceans.
Answer:
1. The density of the crust below the continents is 2.65 to 2.90 gm/cm³ The density of the crust below the oceans is 2.90 to 3.3 gm/cm³

2. As the density of the crust below the continents is comparatively low, it keeps floating on the mantle. It does not subduct into mantle. As its effect, the thickness of the crust below the continents is found to be high.

3. As the density of the crust below the ocean is comparatively high, it subducts into mantle leading to its low thickness. Thus, the thickness of the crust below the continents is more as compared to oceans.

Question E.
Earth is protected because of the magnetosphere.
Answer:

1. The ozone layer protects the earth from ultraviolet radiation.
2. The earth’s magnetosphere serves to deflect most of the solar wind, whose charged particles would otherwise strip away the ozone layer. In this way, the earth is protected because of the magnetosphere.

Know this too:

1. The average density of the earth is 5.5 gm/cm³.
2. The rocks in the upper 100 to 200 km of. the mantle melt due to heat.
3. The mixture of molten rocks, volatiles, etc. found beneath the surface of the earth is called magma.
4. The mixture of molten rocks, volatiles, etc. erupted from volcano or fissure on the surface of the earth is called lava.

Activity:

Question 1.
Prepare a model of the earth’s interior.
Answer:

1. The density of the earth goes on increasing from its surface to the centre.
2. The average density of the crust of the earth is approximately 2.98 gm/cm³.
3. The average density of the mantle of the earth is approximately 5.7gm/cm³.
4. The average density of the outer core of the earth is approximately 9.8 gm/cm³.
5. The density of the inner core at the centre of the earth is approximately 13 gm/cm³.

Class 8 Geography Chapter 2 Interior of the Earth Additional Important Questions and Answers

Tick [✓] the correct options in the box:

Question A.
Which seismic waves can travel through liquid medium?
(a) Primary waves [ ]
(b) Secondary waves [ ]
(c) Surface waves [ ]
(d) Oceanic waves [ ]
Answer:
(a) Primary waves [✓]

Question B.
Which of the following layers of the earth has the highest density?
(a) Crust [ ]
(b) Mantle [ ]
(c) Outer core [ ]
(d) Inner core [ ]
Answer:
(d) Inner core [✓]

Question C.
Which of the following waves can travel through all the layers of the interior of the earth?
(a) Primary [ ]
(b) Secondary [ ]
(c) Tertiary [ ]
(d) Surface [ ]
Answer:
(a) Primary [✓]

Question D.
Which of the following layers of the interior of the earth is in solid form and cool?
(a) Crust [ ]
(b) Mantle [ ]
(C) Outer core [ ]
(d) Inner core [ ]
Answer:
(a) Crust [✓]

Examine the statements and incorrect ones :

Question A.
As we move deeper the surface, temperature keeps decreasing.
Answer:
Incorrect.
Correct statement: As we move deeper the surface, temperature keeps increasing.

Question B.
Magma chambers are found in lower mantle.
Answer:
Incorrect.
Correct statement: Magma chambers are found in upper mantle.

Question C.
The discontinuity is found between the crust, mantle and core.
Answer:
Correct.

Answer the following questions in one sentence each:

Question A.
In which of the layers of the interior of the earth is magma formed?
Answer:
Magma is formed in the mantle (upper mantle) of the earth.

Question B.
What are the two parts of the core?
Answer:
Outer core and inner core are the two parts of the core.

Match the columns and complete the chain :

Question A.

‘A’ Column (The layer of the interior of the earth)	‘B’ Column (Density)	‘C’ Column (Elements found)
1. Sial	(i) 13.3 gm/cm3	(a) Silica and Magnesium
2. Sima	(ii) 2.65 to 2.90 gm/cm3	(b) Nickel and Iron
3. Inner core	(iii) 2.90 to 3.3 gm/cm3	(c) Silica and Aluminium

Answer:

‘A’ Column (The layer of the interior of the earth)	‘B’ Column (Density)	‘C’ Column (Elements found)
1. Sial	(ii) 2.65 to 2.90 gm/cm3	(c) Silica and Aluminium
2. Sima	(iii) 2.90 to 3.3 gm/cm3	(a) Silica and Magnesium
3. Inner core	(i) 13.3 gm/cm3	(b) Nickel and Iron

Answer the following questions in brief:

Question A.
Describe the changes that take place in the temperatures from the surface of the earth to its centre.
Answer:

1. The process of cooling of the earth started from the surface. The temperature goes on increasing from the surface towards the core.
2. The surface of the earth is cool and solid.
3. The centre of the earth is extremely hot. The temperature at the centre of the earth is around 5500° to 6000° C.

Question B.
Describe the changes that take place in the density of the earth from its surface to the centre.
Answer:

1. The density of the earth goes on increasing from its surface to the centre.
2. The average density of the crust of the earth is approximately 2.98 gm/cm³.
3. The average density of the mantle of the earth is approximately 5.7gm/cm³.
4. The average density of the outer core of the earth is approximately 9.8 gm/cm³.
5. The density of the inner core at the centre of the earth is approximately 13 gm/cm³.

Question C.
Write in brief about the travelling of various types of earthquake waves through the layers of interior of the earth.
Answer:

1. The primary earthquake waves travel through the mantle as well as the core of the earth.
2. While travelling through the core of the earth, the direction of the primary earthquake waves gets altered.
3. While travelling through the core, the speed of the primary earthquake waves decreases.
4. The secondary earthquake waves can travel only through the mantle of the earth. These waves get absorbed in the core of the earth. Thus, these waves cannot travel through the core of the earth.

Write short notes on the following:

Question A.
The crust.
Answer:
1. The uppermost layer of the interior of the earth is called the crust. Continental crust and the oceanic crust are the two parts of the crust.

2.The thickness of the continental crust is approximately 16 km to 45 km. On the other hand, the thickness of the oceanic crust is approximately 7 km to 10 km

3. The density of the continental crust is approximately 2.65 to 2.90 gm/cm. On the other hand, the density of the oceanic crust is approximately 2.65 to 2.90 gm/cm³.

4. Silica and aluminium are the main elements found in the continental crust. Therefore, it is also called Sial. On the other hand, Silica and Magnesium are the main elements found in the oceanic crust. Therefore, it is also called Sima.

Question B.
The mantle.
Answer:
1. The mantle is located below the crust of the earth. The mantle is divided into the upper mantle and the lower mantle.

2. The thickness of the mantle is approximately 2870 km. The average density of mantle is approximately 4.5 gm/cm³.

3. The rocks in the upper 100 to 200 km of the mantle melt due to the heat and magma is created. Magma chambers are found in this layer of the earth. Due to the heat and pressure, the energy waves are created in mantle. These energy waves move in vertical direction and magma comes out on the surface of the earth by volcanic eruptions.

4. These endogenitic movements continuously occur in the upper layer of the mantle. Therefore, the upper layer of the mantle is known as the asthenosphere.

5. The average thickness of mantle is approximately 2870 km. Its average density is approximately 4.5 gm/cm³. The temperature at the depth of 2400 to 2900 km is around 2200° to 2500° C. The density of the lower mantle is approximately 5.7 gm / cm³.

Question B.
The outer core.
Answer:
1. The outer core is located below the lower mantle.
2. It is located at the depth from 2900 km to 5100 km from the surface of the earth.
3. The average temperature of the outer core of the earth is around 5000° C. The density of the outer core of the earth is approximately 9.8 gm/cm.

4. The secondary earthquake waves cannot travel from the core of the earth. Therefore, it is inferred that the outer core of the earth must be in liquid or semi-liquid form. The primary earthquake waves can travel from the outer core of the earth.
5. The vertical currents originate in the outer core of the earth.

Question C.
The inner core.
Answer:

1. The inner core is located below the upper core.
2. It is located at the depth from 5150 km to 6371 km from the surface of the earth.
3. The average temperature of the inner core of the earth is around 6000° C. The density of the inner core of the earth is approximately 13.3 gm/cm³.
4. The elements, viz. Iron (Ferrous) and Nickel (Ni) are mainly found in the inner core of the earth. Therefore, it is also called Nife.
5. The temperature at the centre of the earth is almost equivalent to the surface temperature of the sun.

Give geographical reasons for the following:

Question A.
The secondary waves of earthquake cannot travel through the core of the earth.
Answer:

1. The secondary waves of earthquake can travel only through the solid state of the interior of the earth.
2. The outer core of the centre of the earth is in liquid state. Therefore, the secondary waves of earthquake cannot travel through the core of the earth.

Question B.
The inner core is called Nife.
Answer:

1. The inner core predominantly comprises iron and nickel.
2. The word Nife is derived from the word Nickel (Ni) and Iron (Ferrous) (Fe). Therefore, the inner core is called (Ni + Fe) Nife.

Question C.
The upper layer of the crust is called Sial.
Answer:

1. The rocks in the upper layer of the crust have predominance of the compounds of silicon and aluminium.
2. The word Sial is derived from the word Silica (Si) and Aluminium (Al). Therefore, the upper layer of the crust is called (Si + Al) Sial.

Question D.
The lower layer of the crust is called Sima.
Answer:

1. The rocks in the lower layer of the crust have predominance of the compounds of silicon and magnesium.
2. The word Sima is derived from the word Silica (Si) and Magnesium. (Ma). Therefore, the lower layer of the crust is called (Si + Ma) Sima.

Study the following map/ figure /graph and answer the following questions : 

Question A.
At what depth does the curve of the secondary waves seem to have ended in figure (A)?
Answer:
The curve of the secondary waves seems to have ended around the depth of 2900 km in figure (A).

Question B.
What is the velocity of the secondary waves around the boundary of the outer core shown in figure (A)?
Answer:
The velocity of the secondary waves is 6 to 8 km/sec around the boundary of the outer core shown in figure (A).

Question C.
What conclusion can be drawn on the basis of the curve of the secondary waves stopping around the depth of 2900 km?
Answer:
On the basis of the curve of the secondary waves stopping around the depth of2900 km, it can be concluded that secondary waves do not enter the core.

Question D.
What is the velocity of the primary waves at the time of entering the outer core shown in figure (A)?
Answer:
The velocity of the primary waves at the time of entering the outer core shown in figure (A) is 8 km/sec.

Question E.
What conclusions can be drawn about the intensity of the gravitational force shown in Figure (B)?
Answer:
The following conclusions can be drawn about the intensity of the gravitational force shown in Figure (B):

1. Gravitational force increases at certain depth from the surface of the earth and then it reduces according to the depth.
2. At the centre of the earth, the gravitational force is zero.

Thought-Provoking Question:

Think about it:

Question 1.
Imagine about the earth’s interior and- write 10-12 sentences on it.
Answer:

1. The interior of the earth will be very hot.
2. Huge sized rocks will be present I in the upper layers of the interior of the earth.
3. Due to extreme heat and pressure, the rocks must be melting in the interior of the earth.
4. Due to the melting of the rocks, magma will be created in the interior of the earth.
5. Due to endogenous movements in the interior of the earth, volcanic eruptions will occur on the surface of the earth.
6. The primary earthquake waves will be travelling through the mantle and the core of the earth.
7. The secondary earthquake waves will be travelling only through the mantle of the earth.
8. The temperature in the interior of the earth will get increased with the depth.
9. The highest temperature will be found at the centre of the earth.
10. The elements like silica, aluminium, magnesium, iron and nickel will be found in the various layers of the interior of the earth.

Open-Ended Question:

Question A.
What precautions can be taken to reduce the damage caused by earthquakes?
Answer:
The following precautions can be taken to reduce the damage caused by earthquakes:

1. Taking cover under a desk or a table or sturdy piece of furniture to protect oneself.
2. Finding clear spot away from buildings, trees and power lines. Dropping to the ground and staying there until the shaking stops.
3. Switching off the power supply, gas in-home/office, etc.
4. Helping the victims at the earliest.

8th Std Geography Questions And Answers:

• Local Time and Standard Time Class 8 Geography Questions And Answers
• Interior of the Earth Class 8 Geography Questions And Answers
• Humidity and Clouds Class 8 Geography Questions And Answers
• Structure of Ocean Floor Class 8 Geography Questions And Answers
• Ocean Currents Class 8 Geography Questions And Answers
• Land Use Class 8 Geography Questions And Answers
• Population Class 8 Geography Questions And Answers
• Industries Class 8 Geography Questions And Answers
• Map Scale Class 8 Geography Questions And Answers
• Field Visit Class 8 Geography Questions And Answers

Balbharti Maharashtra State Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor Notes, Textbook Exercise Important Questions and Answers.

Class 8 Geography Chapter 4 Structure of Ocean Floor Questions And Answers Maharashtra Board

Structure of Ocean Floor Class 8 Questions And Answers Chapter 4 Maharashtra Board

Class 8 Geography Chapter 4 Structure of Ocean Floor Textbook Questions and Answers

1. Choose the correct option:

Question a.
Like there are landforms on land, ocean floor also has submerged landforms because ………….
(i) there is land under water
(ii) there are volcanoes under water
(iii) land is continuous and there is water in deeper parts
(iv) though land is continuous, its level is not the same everywhere like that of water
Answer:
(iv) though land is continuous, its level is not the same everywhere like that of water

Question b.
Which part of the ocean floor is most useful to the man?
(i) Continental shelf
(ii) Continental slope
(iii) Abyssal plains
(iv) Marine deeps
Answer:
(i) Continental shelf

Question c.
Which one of the following option is related to marine deposits?
(i) Rivers, glaciers, continental shelf, remains of plants and animals
(ii) Volcanic ash, continental shelf, remains of plants and animals
(iii) Volcanic ash, lava, fine particles of soil
(iv) Volcanic ash, remains of plants and animals, abyssal plants
Answer:
(iii) Volcanic ash, lava, fine particles of soil

2. Question a.
Name the landforms shown in the following figure.
(Note: The answer is given directly.)

Answer:

Question b.
Which of these landforms are useful for deep sea research?
Answer:
Submarine plateau and marine trench are the landforms useful for deep sea research.

Question c.
Which of these are appropriate to be used for the protection of marine borders and naval base building?
Answer:
Continental shelf is appropriate to be used for the protection of marine borders and naval base building.

3. Give geographical reasons:

Question a.
The study of ocean floor is useful to man.
Answer:

1. Various minerals, rocks, fine I soil particles are found on the sea floor.
2. Remains of marine plants and animals are also found on the ocean floor.
3. To study the marine life, mineral wealth as well as the process of volcanic eruption, the study of ocean floor is useful to man. ‘

Question b.
The continental shelf is a paradise for fishing activity.
Answer:

1. Being a shallowest part of the ocean bed, sunlight reaches up to continental shelf easily.
2. As its effect, algae, plankton, etc. grows on a large scale on continental shelf.
3. Algae, plankton, etc. is food for fish. Therefore, fish are found on a large scale on continental shelf. Therefore, the continental shelf is paradise for fishing activity.

Question c.
Some marine islands are actually the peaks of sea mountains.
Answer:

1. The hundreds of kilometres wide and thousands of kilometres long hills found on the ocean bed are called submerged hills.
2. Peaks of some of the submerged hills come above the sea level.
3. These peaks are the visible land areas surrounded from all sides by water. These peaks are called islands. Thus, some marine islands are actually the peaks of sea mountains.

Question d.
The continental slope is considered to be the boundary of continents.
Answer:

1. Continental slope lies beyond the continental shelf.
2. The deep abyssal plain begins beyond the continental slope. Therefore, the continental slope is considered to be the boundary of continents.

Question e.
The disposal of waste materials in the oceans by man is harmful to the 1 environment.
Answer:

1. The disposal of waste materials in the oceans by man increases the pollution of sea water.
2. This disposed waste materials harm the life of marine animal life and marine plant. Thus, the disposal of waste materials in the oceans by man is harmful to the environment.

4. Observe the map on Pg 27 in ‘Give it a try’ and answer the following questions:

Question a.
Madagascar and Sri Lanka are related to which landform of the ocean floor?
Answer:
Madagascar and Sri Lanka are related to island of the ocean floor.

Question b.
Near which continent are these landforms located?
Answer:
Madagascar is located near the continent of Africa and Sri Lanka is located near the continent of Asia.

Question c.
Which islands in our country are examples of peaks of submerged mountains?
Answer:
Andaman and Nicobar islands in our country are examples of peaks of submerged mountains.

Activity:

Question a.
prepare a model of the ocean floor.
Answer:

1. While studying the ocean floor, we must keep in mind the age of the ocean bed. By studying the deposits on the ocean bed, it occurred to the scientists that the deposits at the ocean floor are not older than 200 million years.

2. The maximum age of the rocks on the continents is supposed to be 3200 million years. Then where have the deposits on the sea bed which are older than 200 million years gone? This made the scientists restless. Then they started the study of the rocks along with the deposits.

3. This made them realize that the rocks are also not older than 200 million years. It was inferred that the ocean floor is very young as compared to the earth’s surface. Now this is unanimously accepted. This research was then used in the study of the concept of plate tectonics.

Class 8 Geography Chapter 4 Structure of Ocean Floor Additional Important Questions and Answers

Choose the correct answer and complete the sentences:

Question a.
Continental slope has slope.
(a) flatter
(b) broader
(c) steeper
(d) lower
Answer:
(c) steeper

Question b.
The average depth of the oceans is around metres.
(a) 7300
(b) 3700
(c) 3900
(d) 3300
Answer:
(b) 3700

Examine the following statements and correct the incorrect ones:

Question a.
Abyssal plain lies beyond the continental shelf.
Answer:
Incorrect.
Correct statement: Abyssal plain lies beyond the continental slope.

Question b.
Around 51 per cent of the surface of the earth is covered by water.
Answer:
Incorrect.
Correct statement: Around 71 per cent of the surface of the earth is covered by water.

Question c.
Natural gas and mineral oil can be obtained from the continental shelf.
Answer:
Correct.

Question d.
For survey purpose in India, the height of sea level at Kanyakumari is considered to be zero.
Answer:
Incorrect.
Correct statement: For survey purpose in India, the height of sea level at Chennai is considered to be zero.

Question e.
Active volcanoes are mostly seen in marine trenches.
Answer:
Correct.

Answer the following questions in one sentence each:

Question a.
What is called continental shelf?
Answer:
The land near the coast and submerged under the sea is called continental shelf.

Question b.
What is called continental slope?
Answer:
The steeper slope of the sea bed beyond the extent of continental shelf is called continental slope.

Question c.
What is called abyssal plain?
Answer:
The flat part of the sea bed that lies
beyond the continental slope is called abyssal plain.

Question d.
What is called submerged hills?
Answer:
The hundreds of kilometres wide and thousands of kilometres long hills found on the ocean bed are called submerged hills.

Question e.
What is called marine islands?
Answer:
Peaks of some of the submerged hills that come above the sea level are called marine islands.

Question f.
What is called submarine plateau?
Answer:
The flat and extensive summit of marine island is called submarine plateau.

Question g.
What is called marine deep?
Answer:
The landforms on the ocean bed that are comparatively less extending and shallower ones are called marine deep.

Question h.
What is called marine trench?
Answer:
The landforms on the ocean bed that are comparatively more extending and deeper ones are called marine trench.

Match the columns and complete the chain:

Question a.

‘A’ Column	‘B’ Column	‘C’ Column
1. Andaman – Nicobar	(i) Submarine plateau	(a) Pacific Ocean
2. Chagos	(ii) Located on continental shelf	(b) Bay of Bengal
3. Mariana	(iii) Islands	(c) Arabian Sea
4. Mumbai High	(iv) Marine deep	(d) Indian Ocean

Answer:

‘A’ Column	‘B’ Column	‘C’ Column
1. Andaman – Nicobar	(iii) Islands	(b) Bay of Bengal
2. Chagos	(i) Submarine plateau	(d) Indian Ocean
3. Mariana	(iv) Marine deep	(a) Pacific Ocean
4. Mumbai High	(ii) Located on continental shelf	(c) Arabian Sea

Answer the following questions in brief:

Question a.
What is marine deposits?
Answer:

1. Marine deposit is a type of marine deposition.
2. The rivers and glaciers flowing from the continent bring pebbles, clay, soil, etc. with them when they meet sea or ocean.
3. These materials get deposited on the continental shelf. The deposits are known as marine deposits.
4. Due to pressure of sea water and deposition of layers over layers of sediments, sedimentary rocks are formed.
5. Marine life and the availability of minerals in the sea bed can be studied with the help of marine deposits.

Question b.
What is marine oozes?
Answer:

1. Marine oozes is a type of marine deposit.
2. Lava and ash erupting out of volcano, fine soil particles, remains of plants and animals, etc. get deposited on marine abyssal plains. Deposits of these materials on the abyssal plains are known as marine oozes.
3. Marine oozes are in the form of fine clay. The percentage of remains of plants and animals in marine oozes is up to 30 per cent.
4. Marine oozes are also useful to study marine life and the availability of minerals in the sea bed.

Question c.
Write in brief about the continental shelf.
Answer:
1. The land near the seacoast and submerged under the sea is called continental shelf. The depth of continental shelf is about 200 metres below the sea level.

2. Continental shelf is found to be narrow along the coasts of some continents and broad along the coasts of some other continents.

3. Being a shallowest part of the ocean bed, sunlight reaches up to continental shelf easily. As its effect, the food for fish like algae, plankton, etc. grows on a large scale on continental shelf. Therefore, continental shelf is useful for fishing occupation.

4. Various minerals, natural gas and mineral oil, etc. can also be obtained from mining the continental shelf. For example, Mumbai High located on the continental shelf of the Arabian Sea is a source from where the mineral oil and natural gas is obtained.

Question d.
Write in brief about the continental slope.
Answer:

1. The steep slope of the sea bed beyond the extent of continental shelf is called continental slope.
2. The depth of the continental slope is from 200 metres to 3600 metres below the sea level.
3. The continental slope is found to be comparatively narrower.
4. The lower boundary of the continental slope is considered as the boundary of I continent.

Question f.
Write in brief about the abyssal plains.
Answer:

1. The flat part of the sea bed that lies beyond the continental slope is called abyssal plains.
2. Various submerged landforms like
   submerged hills, submerged mountains, etc. are seen on abyssal plains.
3. Submarine plateaus are also found on the abyssal plains.

Question g.
Write in brief about mean sea level.
Answer:

1. The average of the highest high tide and the lowest low tide is considered to calculate the mean sea level.
2. This average is considered to be zero sea level.
3. The altitude of any place above the sea level is measured and expressed in positive value. (For example, Mount Everest is 8848 metres high.)
4. The depth of any place below the sea level is measured and expressed in negative value. (For example, Mariana Trench is 11034 metres below sea level.)

Study the following map/figure/graph and answer the following questions:

Can you tell?

Question a.
What parameters were used for classifying the landforms on the earth?
Answer:
Altitude and the shape of the land were the parameters used for classifying the landforms on the earth.

Question b.
What parameters were used for naming the landforms below water?
Answer:
Depth from the seafloor and the shape of the land were the parameters used for naming the landforms below water.

Give it a try.

Question a.
Name the submerged landforms shown in the diagram.
(Note: The answer is given directly.)

Answer:

Question b.
Identify the ocean shown in the map of the ocean floor.
Answer:
The ocean shown in the map of the ocean floor is Indian Ocean.

Question c.
Which region would be ideal for fishing and why?
Answer:
The region near Madagascar island would be ideal for fishing. Madagascar island has a shallow continental shelf. The warm stream and cold stream also meet near Madagascar island. Therefore, the region near Madagascar island would be ideal for fishing.

2. Name the landforms shown in the following figure and answer the following questions:
(Note: The answer is given directly.)

Question a.

Answer:

Thought-Provoking Questions

Think about it.

Question a.
If the classification of landforms on land can be done on the basis of altitude and size, then how can the landforms submerged underwater are classified?
Answer:
If the classification of landforms on land can be done on the basis of altitude and size, then the landforms submerged underwater are classified on the basis of the depth from the seafloor and the shape of the land there.

Use your brainpower!

Do this activity when you go to the seashore with your parents or teachers. Observe the materials which have come with the waves. Classify them as per the flowchart given below:

Question a.
Which of these are perishable items?
Answer:
Plants, conches and shells, aquatic animals of these are perishable items.

Question b.
Which are non-perishable?
Answer:
Chemicals, metals and plastic/glass are non-perishable.

Question c.
What will happen because of perishable items?
Answer:
Perishable items will not create pollution of seacoast and seawater on a large scale. The remains of perishable items will get deposited in the form of marine oozes on the ocean bed.

Question d.
What will happen because of non-perishable items?
Answer:
Non-perishable items will create pollution of seacoast and seawater on a large scale.

Question f.
Suggest measures to control deposition of non-perishable items on the coast.
Answer:
The following measures can be taken to control deposition of non-perishable items on the coast:

1. Plastic bags, plastic or glass containers must be prohibited on the seacoasts.
2. Strict action must be taken against offenders carrying the banned products on the seacoasts.
3. Hoardings explaining the importance of clean seacoasts must be displayed on all the seacoast.

Question g.
How will you run a campaign of environmental conservation to keep the coasts clean?
Answer:
We will run a campaign of environmental conservation to keep the coasts clean as follows:

1. We will display hoardings explaining the importance of clean seacoasts on the seacoasts.
2. We will arrange street plays, dramas, etc. highlighting the importance of clean seacoasts.
3. We will arrange special programmes during the festivals like Ganeshotsav, Diwali, Christmas, etc. to keep the seacoasts clean.

Open-Ended Questions:

Question a.
Suggest measures to control deposition of non-perishable items on the coast.
Answer:
The following measures can be taken to control deposition of non-perishable items on the coast:

1. Plastic bags, plastic or glass containers must be prohibited on the seacoasts.
2. Strict action must be taken against offenders carrying the banned products on the seacoasts.
3. Hoardings explaining the importance of clean seacoasts must be displayed on all the seacoasts.

Question b.
How will you run a campaign of environmental conservation to keep the coasts clean?
Answer:
We will run a campaign of environmental conservation to keep the coasts clean as follows:

1. We will display hoardings explaining the importance of clean seacoasts on the seacoasts.
2. We will arrange street plays, dramas, etc. highlighting the importance of clean seacoasts.
3. We will arrange special programmes during the festivals like Ganeshotsav, Diwali, Christmas, etc. to keep the seacoasts clean.

8th Std Geography Questions And Answers:

• Local Time and Standard Time Class 8 Geography Questions And Answers
• Interior of the Earth Class 8 Geography Questions And Answers
• Humidity and Clouds Class 8 Geography Questions And Answers
• Structure of Ocean Floor Class 8 Geography Questions And Answers
• Ocean Currents Class 8 Geography Questions And Answers
• Land Use Class 8 Geography Questions And Answers
• Population Class 8 Geography Questions And Answers
• Industries Class 8 Geography Questions And Answers
• Map Scale Class 8 Geography Questions And Answers
• Field Visit Class 8 Geography Questions And Answers

Balbharti Maharashtra State Board Class 8 Maths Solutions covers the Practice Set 1.1 8th Std Maths Answers Solutions Chapter 1 Rational and Irrational Numbers.

Rational and Irrational Numbers Class 8 Maths Chapter 1 Practice Set 1.1 Solutions Maharashtra Board

Std 8 Maths Practice Set 1.1 Chapter 1 Solutions Answers

Question 1.
Show the following numbers on a number line. Draw a separate number line for each example.
i. \(\frac{3}{2}, \frac{5}{2},-\frac{3}{2}\)
ii. \(\frac{7}{5}, \frac{-2}{5}, \frac{-4}{5}\)
iii. \(\frac{-5}{8}, \frac{11}{8}\)
iv. \(\frac{13}{10}, \frac{-17}{10}\)
Solution:
i. \(\frac{3}{2}, \frac{5}{2},-\frac{3}{2}\)

Here, the denominator of each fraction is 2.
∴ Each unit will be divided into 2 equal parts.

ii. \(\frac{7}{5}, \frac{-2}{5}, \frac{-4}{5}\)

Here, the denominator of each fraction is 5.
∴ Each unit will be divided into 5 equal parts.

iii. \(\frac{-5}{8}, \frac{11}{8}\)

Here, the denominator of each fraction is 8.
∴ Each unit will be divided into 8 equal parts.

iv. \(\frac{13}{10}, \frac{-17}{10}\)

Here, the denominator of each fraction is 10.
∴ Each unit will be divided into 10 equal parts.

Question 2.
Observe the number line and answer the questions.

i. Which number is indicated by point B?
ii. Which point indicates the number \(1\frac { 3 }{ 4 }\) ?
iii. State whether the statement, ‘the point D denotes the number \(\frac { 5 }{ 2 }\) is true or false.
Solution:
Here, each emit is divided into 4 equal parts.
i. Point B is marked on the 10th equal part on the left side of O.
∴ The number indicated by point B is \(\frac { -10 }{ 4 }\).

ii.

Point C is marked on the 7th equal part on the right side of O.
∴ The number \(1\frac { 3 }{ 4 }\) is indicated by point C.

iii. True
Point D is marked on the 10th equal part on the right side of O.
∴ D denotes the number \(\frac{10}{4}=\frac{5 \times 2}{2 \times 2}=\frac{5}{2}\)

Std 8 Maths Digest

• Practice Set 1.1 Class 8 Answers
• Practice Set 1.2 Class 8 Answers
• Practice Set 1.3 Class 8 Answers
• Practice Set 1.4 Class 8 Answers
• Practice Set 2.1 Class 8 Answers
• Practice Set 2.2Class 8 Answers
• Practice Set 2.3 Class 8 Answers

Balbharti Maharashtra State Board Class 8 Maths Solutions covers the Practice Set 11.2 8th Std Maths Answers Solutions Chapter 11 Statistics.

Statistics Class 8 Maths Chapter 11 Practice Set 11.2 Solutions Maharashtra Board

Std 8 Maths Practice Set 11.2 Chapter 11 Solutions Answers

practice set 11.2 8th class Question 1.
Observe the following graph and answer the questions.

i. State the type of the graph.
ii. How much is the savings of Vaishali in the month of April?
iii. How much is the total of savings of Saroj in the months March and April?
iv. How much more is the total savings of Savita than the total savings of Megha?
v. Whose savings in the month of April is the least?
Solution:
i. The given graph is a subdivided bar graph.
ii. Vaishali’s savings in the month of April is Rs 600.
iii. Total savings of Saroj in the months of March and April is Rs 800.
iv. Savita’s total saving = Rs 1000, Megha’s total saving = Rs 500
∴ difference in their savings = 1000 – 500 = Rs 500.
Savita’s saving is Rs 500 more than Megha.
v. Megha’s savings in the month of April is the least.

practice set 11.2 Question 2.
The number of boys and girls, in std 5 to std 8 in a Z.P. School is given in the table. Draw a subdivided bar graph to show the data. (Scale : On Y axis, 1cm = 10 students)

Standard	5th	6th	7th	8th
Boys	34	26	21	25
Girls	17	14	14	20

Solution:

Standard	5th	6th	7th	8th
Boys	34	26	21	25
Girls	17	14	14	20
Total	51	40	35	45

Statistics class 8 practice set 11.1 Question 3.
In the following table number of trees planted in the year 2016 and 2017 in four towns is given. Show the data with the help of subdivided bar graph.

Year\Town	karjat	Wadgaon	Shivapur	Khandala
2016	150	250	200	100
2017	200	300	250	150

Solution:

Year\Town	karjat	Wadgaon	Shivapur	Khandala
2016	150	250	200	100
2017	200	300	250	150
Total	350	550	450	250

Statistics class 8 Question 4.
In the following table, data of the transport means used by students in 8th standard for commutation between home and school is given. Draw a subdivided bar diagram to show the data.
(Scale: On Y axis: 1 cm = 500 students)

Means of commutation\Town	Paithan	Yeola	Shahapur
Cycle	3250	1500	1250
Bus and auto	750	500	500
On foot	1000	1000	500

Solution:

Means of commutation\Town	Paithan	Yeola	Shahapur
Cycle	3250	1500	1250
Bus and auto	750	500	500
On foot	1000	1000	500
Total	5000	3000	2250

Std 8 Maths Digest

• Practice Set 11.1 Class 8 Answers
• Practice Set 11.2 Class 8 Answers
• Practice Set 11.3 Class 8 Answers
• Practice Set 12.1 Class 8 Answers
• Practice Set 12.2 Class 8 Answers
• Practice Set 13.1 Class 8 Answers
• Practice Set 13.2 Class 8 Answers
• Practice Set 14.1 Class 8 Answers
• Practice Set 14.2 Class 8 Answers

Balbharti Maharashtra State Board Class 8 Maths Solutions covers the Practice Set 10.1 8th Std Maths Answers Solutions Chapter 10 Division of Polynomials.

Division of Polynomials Class 8 Maths Chapter 10 Practice Set 10.1 Solutions Maharashtra Board

Std 8 Maths Practice Set 10.1 Chapter 10 Solutions Answers

Question 1.
Divide and write the quotient and the remainder.
i. 21m² ÷ 7m
ii. 40a³ ÷ (-10a)
iii. (- 48p⁴) ÷ (- 9p²)
iv. 40m⁵ ÷ 30m³
v. (5x³ – 3x²) ÷ x²
vi. (8p³ – 4p²) ÷ 2p²
vii. (2y³ + 4y² + 3 ) ÷ 2y²
viii. (21x⁴ – 14x² + 7x) ÷ 7x³
ix. (6x⁵ – 4x⁴ + 8x³ + 2x²) ÷ 2x²
x. (25m⁴ – 15m³ + 10m + 8) ÷ 5m³
Solution:
i. 21m² ÷ 7m

∴ Quotient = 3m
Remainder = 0

ii. 40a³ ÷ (-10a)

∴ Quotient = -4a²
Remainder = 0

iii. (- 48p⁴) ÷ (- 9p²)

∴ Quotient = \(\frac { 16 }{ 3 }\) p²
Remainder = 0

iv. 40m⁵ ÷ 30m³

∴ Quotient = \(\frac { 4 }{ 3 }\) m²
Remainder = 0

v. (5x³ – 3x²) ÷ x²

∴ Quotient = 5x – 3
Remainder = 0

vi. (8p³ – 4p²) ÷ 2p²

∴ Quotient = 4p – 2
Remainder = 0

vii. (2y³ + 4y² + 3 ) ÷ 2y²

∴ Quotient = y + 2
Remainder = 3

viii. (21x⁴ – 14x² + 7x) ÷ 7x³

∴ Quotient = 3x
Remainder = -14x² + 7x

ix. (6x⁵ – 4x⁴ + 8x³ + 2x²) ÷ 2x²

∴ Quotient = 3x³ – 2x² + 4x + 1
Remainder = 0

x. (25m⁴ – 15m³ + 10m + 8) ÷ 5m³

∴ Quotient = 5m – 3
Remainder = 10m + 8

Maharashtra Board Class 8 Maths Chapter 10 Division of Polynomials Practice Set 10.1 Intext Questions and Activities

Question 1.
Fill in the blanks in the following examples. (Textbook pg. no. 61)

1. 2a + 3a = __
2. 7b – 4b = __
3. 3p × p² = __
4. 5m² × 3m² = __
5. (2x + 5y) × \(\frac { 3 }{ x }\) = __
6. (3x² + 4y) × (2x + 3y) = __

Solution:

1. 2a + 3a = 5a
2. 7b – 4b = 3b
3. 3p × p² = 3p³
4. 5m² × 3m² = 15m⁴
5. (2x + 5y) × \(\frac { 3 }{ x }\) = \(6+\frac { 15y }{ x }\)
6. (3x² + 4y) × (2x + 3y) = 6x³ + 9x²y + 8xy + 12y²

Std 8 Maths Digest

• Practice Set 8.1 Class 8 Answers
• Practice Set 8.2 Class 8 Answers
• Practice Set 8.3 Class 8 Answers
• Practice Set 9.1 Class 8 Answers
• Practice Set 9.2 Class 8 Answers
• Practice Set 10.1 Class 8 Answers
• Practice Set 10.2 Class 8 Answers