Topic outline

    • Water: A Precious Resource

      Q1. Fill in the blanks.

                                  i.        People obtain groundwater through tube wells and handpumps.

                                 ii.        Three forms of water are solid, liquid and gas.

                                iii.        The water bearing layer of the earth is aquifer.

                                iv.        The process of water seepage into the ground is called infiltration.

                                v.        The amount of water recommended by the United Nations for drinking, washing, cooking and maintaining proper hygiene is a minimum of 50 litres per person per day.


      Q2. True/False

                                 i.        The freshwater stored in the ground is much more than that present in the rivers and lakes of the world. True

                                ii.        Water shortage is a problem faced only by people living in rural areas. False

                               iii.        Water from rivers is the only source for irrigation in the fields. False

                               iv.        Rain is the ultimate source of water. True

                                v.        Bawri was the traditional way of collecting water. True

      Q3. When is water day celebrated?

      Ans. 22 March is celebrated as the world water day.


      Q4. What is ground water?

      Ans. The water found below the water table is called groundwater.


      Q5. What is infiltration?

      Ans. The process of seeping of water into the ground is called infiltration.


      Q6. Why do we celebrate world water day?

      Ans. We celebrate water day every year to attract the attention of everybody towards the importance of conserving water.


      Q7. What is aquifer?

      Ans. At places the groundwater is stored between layers of hard rock below the water table. This is known as an aquifer.


      Q8. What are the main processes involved in the water cycle?

      Ans. The main processes involved in the water cycle are evaporation, transpiration, condensation, precipitation, runoff, and percolation.

      Q9. Why is the water cycle important?

      Ans. The water cycle is important because its process provides Earth with the natural, continual water supply all living things need in order to survive.


      Q10. What is the source of groundwater?

      Ans. 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.


      Q11. How is water supplied in town?

      Ans. Most towns and cities have water supply system maintained by the civic bodies. The water is drawn from nearby lakes, rivers, ponds or wells. The water is supplied through a network of pipes.


      Q12. What is rainwater harvesting?

      Ans. Most of the water that we get as rainfall just flows away. This is a waste of precious natural resource. The rainwater can be used to recharge the groundwater. This is referred to as water harvesting or rainwater harvesting.


      Q13. You have been asked to maintain a garden. How will you minimise the use of water?

      Ans. We can use drip irrigation to minimise the use of water. Drip irrigation is a technique of watering plants by making use of narrow tubings which deliver water directly at the base of the plant.

      Q14. There are ten tube wells in a lane of fifty houses. What could be the long term impact on the water table?

      Ans. The water table does not get affected as long as we draw as much water as is replenished by natural processes. However, water table may go down if the water is not sufficiently replenished.


      Q15. How can farmer use water economically?

      Ans. A farmer using water in the field can also use water economically by using drip irrigation technique. Drip irrigation is a technique of watering plants by making use of narrow tubings which deliver water directly at the base of the plant.


    • Download to practice offline.