Water resources

1. Why is water essential for maintaining life?

Ans-We use water for drinking , bathing , washing , and cooking. With out water we can not think of our daily life. So water is essential for maintaining life.
2. What are the sources of water in villages and cities ?
Ans- The people in village get water from wells , ponds and rivers and people in cities are dependent upon municipal taps. There are tube well that supply water at some places.
3. How is  water polluted in village ponds ?
Ans- In village some people bathe in ponds . They also wash their clothes there. Even the animals bathe in some ponds. In this way the water is polluted in village ponds.
4.  Howcan we conserve water ?
Ans- we can conserve to water to use it wisely . We must always check that the taps water is not being .we should not pollute the water.
5. Why do we need water for irrigation ?
Ans- water is essential for growth of crops . We water the plants to enable them to grow. So we need for irrigation.
6. Why can we not depend on rains for irrigation ?
Ans- Rains are not certain in our country. They may not came in time to people the crops . So we can not depend on rain for irrigation .
7. Write down any two uses of dams.?
Ans- Two uses of dams are :- a)  It saves the water of our rivers for irrigation.
b) It controls floods in the rivers.
8. Name any three Multi-purpose River Projects of our country.
Ans- The multi purpose rivers projects our country are :- 
a) Bhakra Nangal
b) Kosi
c) Nagarjuna Sagar and
d) Hirakud
9. How is electricity produced at the dams ?
Ans – The water in the clams falls on big wheels and turns them . The wheels turn the machine which produce electricity.
10. Which is said to be one of the biggest man-made lakes in the world ?
Govinda sagar lake is one of the biggest man-made lakes in the world .
11.  What is the importance of the Bhakra Dam ? Across which river has it been built ?
Ans – The importance of the Bhakra Dam is it supplies water for irrigation to Punjab and other states . It is built across Sutlej river.

Say true or false.

1. We need water for daily use and irrigation.(T)
2. There are no pollution in rivers. (F)
3. Canals are a means of irrigation. (T)
4. Dams serve only one purpose- irrigation.  (F)

Match the following

• Bhakra Dam a)  Bihar and Nepal
• Kosi Dam b)  Punjab                                                    and Haryana
• Damodar valley c)  Jharkhand.                                            and west Bengal
• Hirakud Dam d)  Orissa