Rajasthan Board RBSE Class 7 Social Science Chapter 3 Water
RBSE Class 7 Social Science Water Intext Questions and Answers
Page No 22.
List the main civilization of the world looking map of ancient civilization.
- Valley Civilization
- Africa Nile Valley civilization
- North America Maya, Ejtak civilization
- South America inka civilization.
Page No 23.
List other cities lying on the water sources by studying map world. You can take help of your teacher.
The cities of world located near water sources:
- Washington D.C. (Potomake river)
- Alexandria (Nile river)
- Reodejenaro (Atlantic ocean)
- Los Angles (Pacific ocean)
- Tokyo (Pacific ocean)
- Bhopal – Bhojtal lake
- Nainital (Nainital lake)
- Kampala (Victoria lake).
Page No 24.
How many oceans are there on earth? List them.
There are four oceans on earth –
- Pacific ocean
- Atlantic ocean
- Indian ocean
- Arctic ocean.
Find out the availability of water per person by observing following map.
From the map it is clear that the availability of water per person is very less in high density population area like India, Sahara Desert, China and Pakistan, Polar region like Canada, Iceland, Norway, Russia etc. have more water compared to their population.
Page No 25.
What is the source of water at your home/school?
Sources of water we use at our home and school are as follows –
List the modes of withdrawing underground water.
Traditional modes of withdrawing underground water are hand pumps and well. Modern modes of withdrawing underground water – water is brought on the surface of earth by machines such as tube-wells and wells.
Page No 27.
List the reason for pollution in water bodies nearby your places? Discuss the effect of using polluted water on organisms in your class.
Reasons of water pollution of sources – Followings are the main reasons of water pollution of sources – The main reasons are – the solid waste from industries and chemicals, domestic waste, use of insecticides and fertilizers, washing of clothes on water bodies, defecation and oil spilling from ships etc.
Harmful effect of using polluted water – Polluted water gives rise to many diseases which result in many harmful effects on both land and aquatic organisms. The availability of soluble oxygen becomes less. Polluted water also causes lots of harm to vegetation and crops too.
Children must identify the polluted sources of water in their surroundings and also identify reasons of their becoming polluted.
Page No 28.
Collect information from newspaper, magazine and internet about water conservation in Rajasthan, India and the world.
Many techniques for water conservation are being adopted in Rajasthan, India and the world such as dam, canal construction, drip and fountain irrigation system, retreating of polluted water and then reuse it and create public awareness. In Rajasthan water is collected at roof during rainfall and stored in tank. Then it is used later on.
List the water sources at your places which are being used from ancient times.
From ancient times lakes, ponds, canals, wells and dams are constructed as water source. These water sources were used for irrigation and fresh potable water.
Was any water source constructed in ancient times at your place? If yes, then collect information about it.
In ancient times, lakes, canals, ponds, wells, dams and step wells were constructed for water conservation with public and government help. In Rajasthan many kings have contributed in water conservation by constructing dams, ponds, canals, wells etc. (Note – Students will collect information themselves regarding construction of water sources in the ancient time).
RBSE Class 7 Social Science Water Text Book Questions and Answers
Choose the correct options:
1. Water day is celebrated on –
(a) 25 March
(b) 22 March
(c) 15 March
(d) 10 March
(b) 22 March
2. Von Lake is in which country?
Fill in the blanks:
- Natural water is getting ………………….. due to human activities.
- In ………………….. of Meghalaya in India receivers maximum rainfall in the world.
- Rainfall when get collected an storage on the rocks below ground is called …………………..
- Salty water is also known as …………………..
- Mosinram and Cherrapunji
- underground water
What is ‘roof top water conservation?
On the roof top rainy water is stored and by Roof top water conservation method, water is released through a pipe on the ground from the water constructed on the roof. Later on, the water is used according to necessity.
Write the various sources of water.
Sources of fresh water on land are – rivers, lakes, dams, canals, wells, underground water etc. Main sources of salty water are – oceans. There are certain sour water lakes on land.
Why ancient civilization developed near shores of water bodies?
All civilizations of the world developed near the shores of water bodies. These civilizations of the world not only used water sources for drinking water but also used for agriculture, business, transport and defence facilities. The main cities of the world developed near rivers, lakes and coastal area. Water is centre of our social, political, religious, cultural and commercial importance.
What problems we face by careless use of underground water?
Level of underground water is decreasing day to today because of its unmindful and careless use. There is a steep decrease in underground water around the world because of low rainfall, more irrigation use, industrial use and rise in population. In the world today, one person of every sixth person is fighting to get fresh water. Because of careless use of water, survival of industries, agriculture and vegetation human life and other organisms can be at stake. As a result land can be unusable due to scarcity of rain and less humidity in the land.
What is the difference between fresh and salty water?
Water which is potable is called as fresh water. In fresh water salt contents are less whereas in salty water, salt contents like sodium, chlorine, calcium, magnesium and other salts are present in large quantity. Because of presence of much salt properties in salty water, this type of water can’t be used for irrigation and for human being necessity.
What is water pollution? Suggest measures for its control.
Water Pollution – The unwanted particles in potable water leads to pollution of water, which makes it unfit for human use. This is called water pollution. Methods to stop water pollution The steps taken to stop water pollution should be individual and administrative.
1. Individual Measures:
- Public should be educated to stop polluting water and its sources.
- We should not use public water bodies for bathing pets, washing clothes, taking bath etc.
- Use of chemical fertilizer should be limited.
2. Administrative level Measures:
- The water of sewage line should be treated well before mixing to water bodies.
- Solid domestic waste should not be thrown in water sources but should be dumped at far away barren land.
- Caws should be made for the people and industries which are causing water pollution. These laws must be enforced strictly.
- People should be made aware of pollution control and protection through television, radio and newspaper.
RBSE Class 7 Social Science Water Important Questions and Answers
Water changes into vapor due to certain temperature, it is called –
Which one of the metro cities is situated at sea coast?
Inka civilization developed in –
(b) North America
(c) South America
(c) South America
On the coast of which river, Delhi is situated?
Which city is situated at the coast of Thames river?
(a) New York
Fill in the blanks:
- Main basis of life is ……………………….. (water/land)
- Keep fresh water for longer by preventing wastage of water is called ……………………….. (conservation/recycle)
- Wind gets vapor from seas, it is called ……………………….. (humidity/vapor)
- Salty water is also called ……………………….. water. (soft/hard)
- ……………………….. plan has been started to clean the rive Ganga. (Ganga Action/Namami Gauge)
- water conservation
- Ganga action/ Namami Gauge.
Select True/False statement out the following:
- Mohsinraain and Cherraputiji in Meghalaya of India receive maximum rainfall in the world.
- Von lake of Turkey is the largest fresh water lake in the world.
- Ratio of water is more in comparison of population at polar regions.
- Quantity of soluble oxygen increases, in polluted water.
- 22 March is celebrate as Water Day every year.
Match the following:
Match the correct city against the name of lakes –
- Lake – City
- Dul – Chicago
- Ieri – Srinagar
- Superior – Battalo
- Michigan – Duluth
- Lake – City
- Dul – Srinagar
- Ieri – Battalo
- Superior – Duluth
- Michigan – Chicago
Very Short Question Answer:
What percentage of potable water of the entire available water on the earth?
Less than 2.5 percent.
Write any two conventional methods of water conservation.
- Lake, pond
- Well and step well.
Write any two modern methods of water conservation.
- Dam or canal construction
- embarkment construction.
Write name of two cities situated near the coast of the Pacific ocean.
Write name of three cities of Rajasthan that are situated on the shore of a river.
Write name of any two cities of India that are situated near the shore of lakes.
What is meant by vaporization?
Change of water into vapor at a certain temperature is called vaporization.
What is meant by evaporation?
Releasing of water in the form of vapor by vegetation is called evaporation.
Due to the presence of which properties water is salty?
The salty nature of water is due to salts like sodium chlorine, calcium, magnesium and other salts present in them.
What is called underground water?
When rain water gets stored on hard rocks beneath land, it is called underground water.
What is called water conservation?
Control over use of water and preserving it for longer use is called water conservation.
Short Question Answer:
What is water pollution?
The unwanted particles in potable water leads to pollution of water, which make it unfit for human use. This is called water pollution.
What are the reasons of water pollution?
Reasons of water pollution – The main reasons of water pollution are – the solid waste from industries and chemicals, domestic waste, use of insecticides and fertilizers, washing of clothes on water bodies, defecation and oil spilling from ships.
State effect of water pollution.
Polluted water is unlit for us. It leads to many diseases. They pollute aquatic life and crops also.
What are the reasons of sharp decrease in fresh water whereas its demand is increasing?
Due to steep rise in population, demand of fresh water also is increasing in the world in the present time. Due to much use of fresh water in irrigation, industrialization, global warming, urbanization, modern life style, low rainfall, destruction of forest etc. fresh water is decreasing rapidly whereas its demand in steeply rising.
Explain conventional water conservation techniques and their utility.
From ancient times lakes, ponds, wells and step wells are constructed for water conservation with public and govt, help. Time to time construction of lakes, their repairing, connecting rivers is an example of water conservation. Conventional water sources form basis of ecology and culture. Conventional water conservation techniques are stronger and more useful for water crisis.
What are modern water conservation techniques being adopts?
Modern water conservation techniques – In modern society many water conservation techniques are being adopted due to water crisis such as –
- construction of dam and canal
- anicut construction
- drip irrigation techniques
- use of polluted water by retreating it
- roof top water conservation techniques etc.
Essay Type Questions:
What is water cycle? State clearly its process.
Water from water sources evaporates and again come hack to them by changing various forms. This whole process is called water cycle.
Process of water cycle –
- Sources of water like rivers, lakes, ponds, sea, underground water etc. get water from rainfall,
- Due to stored and temperature evaporation occurs in these water bodies and transpiration in plants,
- When water vapor rises up the temp, falls down and they condense to form water droplets,
- The condensation forms clouds and these clouds are moved from one place to another by winds,
- clouds fall as rainfall and rain water reaches sea from rivers again. In this way this process of ‘water cycle goes on continuously.
State clearly that the present circumstances are indicating towards much water crisis in future.
The present circumstances are indicating towards much water crisis in near future. Hence as
- Out of every 6th person, one person in the world is lighting to get fresh water,
- By 2050 population of world will be 9 Arabs as per estimate and nearly 50% population of the world will face water crisis very much,
- By 2020, half of the population of the world will be living in cities and it will be a great challenge to supply water to this much population,
- Water is getting very less available due to rise in population, exploitation of underground water, global warming, deforestation, commercial, agriculture, less rainfall, increasing industrialization, urbanization and modern life style.
- On the other hand, demand of fresh water is increasing. Looking at the above circumstances, conditions of worst water crisis will be faced by the people around the world.
List the main cities of world located near rivers, lakes and coastal areas of seas.
Following is the list of the main activities of the world located near rivers, lakes and coastal area of the seas.