Here in this post we provided NCERT Exemplar Problem Class 7 Science Water : A Precious Resource Chapter 16 Full Explanation by group of Science Experts. We have provided here each questions answer with reason behind the answer.
Hope it help you!
Water : A Precious Resource Class 7 Exemplar full Explanation:
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Multiple Choice Questions
1) Which of the following does not show water shortage?
a) Taps running dry.
b) Long queues for getting water.
c) Marches and protests for demand of water.
d) A family gets three buckets of water per person per day.
Answer:- d) A family gets three buckets of water per person per day.
Buckets full of water does not show water shortage. Other options show the shortage of water.
2) Seas and oceans are full of water on earth. However, a very small percentage of water present on earth is available for us. This percentage is roughly
a) 0.006%
b) 0.06%
c) 0.6%
d) 6%
Answer:- a) 0.006%
The percentage of usable water on the earth is roughly 0.006% .
3) Which of the following are not the liquid forms of water ?
i) Snow
ii) Lake water
iii) River water
iv) water vapour
v) Ice
Choose the correct combination form the options below.
a) i,iv and v
b) i, and ii
c) ii and iii
d) iv only
Answer:-a) I, iv and v
Snow , water vapour and ice is not liquid form of water. Other are in liquid form.
4) A man digging the ground near a water body found that the soil was moist. As he kept digging deeper he reached a level where all the spaces between particles of soil and gaps between rocks were filled with water. The upper limit of this layer is called
a) Water level.
b) Water table.
c) Ground water.
d) Water limit.
Answer:-b) water table.
The upper level of water layer is known as water table.
5) Which of the following is a way to use water economically?
a) Construction of bawris
b) Rainwater harvesting
c) Drip irrigation
d) Infiltration
Answer:-c) Drip irrigation
Drip irrigation is a way to use water economically.
6) On which of the following day is world water Day observed?
a) 22 March
b) 14 November
c) 2 October
d) 21 December
Answer:- a) 22 March
22 march is the world water Day.
7) The amount of water recommended by the United Nations for drinking, washing, cooking and maintaining proper hygiene per person per day is a minimum of
a) 5 litres
b) 15 litres
c) 30 litres
d) 50 litres
Answer:- d) 50 litres
Per person per day the minimum amount of water is 50 litres as per recommended by United Nations.
8) “Every Drop Counts” is a slogan related to
a) Counting of drops of any liquid.
b) Counting of water drops.
c) Importance of water.
d) Importance of counting.
Answer:- c) Importance of water .
Every drop counts is the slogan related to importance of water.
9) Water cycle does not involve which of the following?
a) Evaporation
b) Condensation
c) Formation of clouds
d) Rainwater harvesting
Answer:- d) Rainwater harvesting
Water cycle does not involve rainwater harvesting.
10) Which of the following inhibits the seepage of rainwater into ground?
a) A pukka floor
b) Playground
c) Grass lawn
d) Forest land
Answer:- a) A pukka floor
A pukka floor will not also seeping of water into ground.
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Very Short Answer Questions
11) State whether the following statements are true or False. If false, write the correct statement.
a) Water vapour is the gaseous form of water.
Answer:- True
b) Ice is solid whereas snow is the semi- solid form of water.
Answer:- false
Ice is solid whereas snow is also solid form of water.
c) Ocean water cannot be used for domestic purposes.
Answer:- True
d) Rapid growth of industries is one of the causes for water shortage.
Answer:- True
12) Some definitions are given below which can be corrected by changing one word. Correct them.
a) Aquifer is ground water stored between layers of hard rock above the water table.
Answer:- Aquifer is ground water stored between layers of hard rock below the water table.
b) The process of Evaporation of water in the ground is called infiltration.
Answer:- the process of seeping of water in the ground is called infiltration.
c) The evaporation of water from oceans and it’s arrival back into oceans is called vapour cycle?
Answer:- the evaporation of water from oceans and it’s arrival back into oceans is called water cycle.
13) What is the source of water in each of the following?
a) Wells
Answer:- wells get water Fromground water.
b) Ground
Answer:- Ground gets water from Rainwater.
c) Atmosphere
Answer:- atmosphere gets water by Evaporation.
14) State whether the following statements are True or False. If false, give the correct statement.
a) The process of seeping of water into ground is called filtration.
Answer:- False
The process of seeping of water into ground is called Infiltration.
b) 51% of the earth’s surface is covered with water.
Answer:- False.
71% of the earth’s surface is covered with water.
c) Year 2003 was observed as the International year of freshwater.
Answer:- True
d) Snow and ice both are Solid forms of water.
Answer:- True
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Short Answer Questions
15) Fill in the blanks in the given passage.
The rainwater and ____________ from other sources such as rivers and ponds seeps through the __________ and fills the empty spaces and cracks deep below the ground. The process of seeping of water into the ground is called _______.
Answer:-
The rainwater and water from other sources such as rivers and ponds seeps through the soil and fills the empty spaces and cracks deep below the ground. The process of seeping of water into the ground is called infiltration.
16) Fill in the blanks and complete the story selecting words from the box given here.
Cold, demand, leaders, dry, hot , scarcity, workers , wet, oceans, harvesting, rivers.
Rajasthan is a ___________ and dry place. The challenge of natural _________ of water was met by a successful experiment. A band of social ___________ had transformed a ________ area into a green place. They have received five dried – up _________ by constructing water __________ structure.
Answer:-
Rajasthan is a hot and dry place. The challenge of natural scarcity of water was met by a successful experiment. A band of social workers had transformed a dry area into a green place. They have received five dried – up rivers by constructing water harvesting structures.
17) Place the following statements in a proper order to form a meaningful paragraph.
a) Which in turn decrease the seepage of rain water into the ground.
b) This decreases the open areas like park, and playgrounds.
c) Increasing population create demand for construction of houses , shops, offices, roads, and pavements.
d) This results in depletion of water table and creates scarcity of more water.
Answer:-
C) increasing population create demand for construction of houses, shops, office, roads and pavements.
B) this decreases the open areas like parks and playgrounds.
A) which in turn decrease the seepage of rain water into the ground.
D) this results in depletion of water table and creates scarcity of more water.
18) How can you observe the three forms of water in (i) nature and (ii) at home ?
Answer:-
nature – snow, water , water vapour
Home – Ice , water , steam
19) Complete the given table:-
Form of water | Process by which formed | Location where found |
a) Liquid |
|
|
b) Solid |
|
|
c) Gaseous |
|
Answer:-
Form of water | Process by which formed | Location where found |
a) Liquid | Condensation
And Melting |
Rivers
Lakes Wells etc water bodies. |
b) Solid | Freezing
|
Cold regions – high mountain , south pole , north pole etc. |
c) Gaseous | Evaporation
|
Atmosphere |
20) Match the column I with column II.
Column I | Column II |
a) Ground water | i) Solid from of water |
b) bawri | ii) Wastage of water |
c) Snow | iii) Water management |
d) Drip irrigation | iv) Small water |
e) Leaking taps | v) Water table |
Answer:-
a) Ground water → v) water table
b) Bawari → iv) Small water
c) Snow →i) solid form Of water
d) Drip irrigation→ iii) water Management
e) Leaking taps. → ii) wastage of Water.
21) A list of jumbled words are given here. Write the correct form of each word.
a) WASHFERRET
b) CHARREGE
c) QUIFERA
d) WOSN
Answer:-
A) FRESHWATER
B) RECHARGE
C) AQUIFER
D) SNOW
22) From where do the following usually get water ? In which form is water present in them ?
a) Clouds
Answer:- clouds get water from land
It is present in the liquid form in drops of water .
b) Plants
Answer:- plants get water from soil
It is present in liquid form of water .
c) Mountain tops
Answer:- Mountain tops get the water from atmosphere.
It is in the form of solid form.
d) Aquifer
Answer:- aquifer gets the water from rain.
It is present in the form of liquid form underground water .
e) Animals
Answer:- animals get water from water bodies like river, pond, lake etc.
It is present in the form of liquid water.
• Long Answer Questions
23) Complete the following chart by writing appropriate words in the boxes marked (a) to (e).
Answer:-
24) What is ground water? What are the sources of water which are fed by ground water?
Answer:-
On digging a hole in the ground we sometimes find the soil moist inside. The moisture of the soil shows that there is water inside the ground. On further digging inside we may get water which is present in the soil and gaps between the rocks. These upper level of the layer is known as water table. These water table changes from place to place in the depth. If the water found Below the water table then these type of water is known as underground water.
When the rain water falls on the ground it is absorbed by the soil and it gets seep inside the rocks gap in the c-horizon. Where it is stored in the gaps of rocks.
The other sources as river, ponds from these water seep inside and fills the gaps.
The seeping of water means absorption of water inside the ground it is known as infiltration.
The places where the groundwater is stored between layers of big rocks below water tableis known as aquifer .
These water stored in aquifer is usually used by pumping , handpumps and wells.
25) Water is very precious for all the living beings. What will happen in future if we do not save water now?
Answer:-
Water is very important for our life.
We have many time listen the phrase
That , “ Jal hai to , kalhai” and “jal hi jivanhai”this means that without water there is no future for us. We need water for almost everything we do. Main thing we need water for drinking which is the most important work of water in our life. Rather than we need water for our household works.
It is used for plants also which is also important for our daily dose of food. If there will be scarcity of water due to overuse water or wastage of water now then In future we will not be able to do these all things. various works of our day to day life is dependent on the water. Our life will be in Danger without water. We will not get daily drinking water also we will not get food from plants which is also main thing of our life we cannot do without water. Therefore we should not waste water and save the water for future.