Water A Precious Resource
Exercise
1). Mark ‘T’ if the statement is true and ‘F’ if it is false:
a). The freshwater stored in the ground is much more than that present in the rivers and lakes of the world. (T/F)
Ans: True.
b) Water shortage is a problem faced only by people living in rural areas. (T/F)
Ans: False
c). Water from rivers is the only source for irrigation in the fields. (T/F)
Ans: False
d). Rain is the ultimate source of water (T/F).
Ans: True
2). Explain how groundwater is recharged?
Ans: Rainwater and water from other sources such as rivers and ponds seep through the soil and fill the empty spaces and cracks deep below the ground. The process of seeping of water into the ground is called infiltration. The groundwater thus gets recharged by this process.
3). There are ten tubewells in a lane of fifty houses. What could be the long-term impact on the water table?
Ans: Huge amount of water will be pumped out by the tubewells. The water table does not get affected as long as the water drawn is replenished by natural process. However, water table may go down if the water is not sufficiently replenished. In longer time it will affect the water availability of that place.
4). You have been asked to maintain in a garden. How will you minimize the use of water?
Ans: The use of water can be minimized by
(i) using drip irrigation
(ii) preventing leakages in the pipes.
5). Explain the factors responsible for the depletion of water table.
Ans: The factors responsible for the depletion of water table are as follows.
(i) Increasing population
(ii) increasing industries
(iii) Agricultural activities.
6). Fill in the blanks with the appropriate answers:
a). People obtain groundwater through tubewells and hand pumps.
b). Three forms of water are solid, liquid and gas.
c). The water-bearing layer of the earth is the water table.
d). The process of water seepage into the ground is called infiltration.
7). Which one of the following is not responsible for water shortage?
(i). Rapid growth of industries
(ii) Increasing population
(iii) Heavy rainfall
(iv) Mismanagement of water resources
Ans: Heavy rainfall.
8). Choose the correct option. The total water
(i) in the lakes and rivers of the world remains constant.
(ii) under the ground remains constant.
(iii) in the seas and oceans of the world remains constant.
(iv) of the world remains constant.
Ans: of the world remains constant.
9). Make a sketch showing groundwater and water table. Label it.
Additional Questions
Fill in the blanks.
(i). 22nd March is celebrated as World Water Day.
(ii). Year 2003 was observed as the International Year of the Freshwater.
(iii). The moisture in the soil indicates the presence of water underground.
(iv). Water drawn from under the ground gets restored by seepage of rainwater.
(v). Excessive rains cause floods, whereas the absence of rain results in droughts.
(vi). Bawri was the traditional way of collecting water.
True or false.
(i). The amount of water recommended by the United Nations for drinking, washing, cooking, and maintaining proper hygiene is a minimum of 15 litres per person per day.
Ans: False
(ii) About 71% of the earth’s surface is covered with water.
Ans: True.
(iii). The water table varies from place to place.
Ans: True
(iv). Water in the aquifers can be usually pumped with the help of tube wells or handpumps.
Ans: True
(v). The distribution of water over the globe is even.
Ans: False
(vi). Bawri was the traditional way of collecting water.
Ans: True.
(vi). Bawris are revived.
Ans: True.
Define.
i). infiltration
Ans: The process of seeping of water into the ground is called infiltration.
ii). Aquifer
Ans: The groundwater stored between the layers of hard rock below the water table is known as aquifer.
Answer the following questions.
1). What percent of the earth’s surface is covered with water?
Ans: 71%.
2). Write the three forms of water.
Ans: The three forms of water are solid, liquid and gases.
3). What is groundwater?
Ans: The water found below the water table is called as groundwater.
4). What is rainwater harvesting?
Ans: The rainwater can be used to recharge the groundwater. This is referred to rainwater harvesting.
5). What is drip irrigation?
Ans: Drip irrigation is a technique of watering plants by making use of narrow tubings which deliver water directly at the base of the plant.
Click here for the solutions of
6). Physical and Chemical Changes
7). Weather, Climate and Adaptations of Animals to Climate
8). Winds, Storms and Cyclones
11). Transportation in Animals and Plants
14). Electric Currents and its Effects
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