STD 6- SCIENCE- WATER IS LIFE- NOTES

Water is Life

1 Explain how drought  causes extensive damage to human life and property?

ANS:      

1.             Droughts results in dying up of the crops and vegetation.

2.             Its leads to scarcity of food and fodder for humans and animal life respectively.

3.             Its leads to malnutrition in human and animals.

2. Explain how ground water is recharged?

ANS:  Trees help in recharging the ground water supply. The roots of the tree grow and spread in the soil. This helps in creating open spaces in the soil. 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. By this process groundwater gets recharged.

3.Explain the factors responsible for the depletion of water table?

ANS: 

1.             Increase in population

2.             Increase in agriculture activities,

3.             Rapid Urbanization,

4.             Deforestation,

5.             Mismanagement of water resources

4.             When does a drought occur?

ANS:  When there is insufficient or no rainfall occurs for more than a year in a region, the scarcity of water happens. Ponds and wells dry up. The soil continues to lose water due to evaporation and transpiration and eventually dry. This leads to drought.

       5. Why is there a need for conserving water? Give two reasons.

ANS: 1. Increasing population need more water.

2. Availability of water is decreasing day-by-day.

6.             What is rainwater harvesting? What are the two rainwater harvesting techniques?

ANS:  Collecting rain water and storing it for later use is called rainwater harvesting. The two techniques of harvesting are:

1.             Rooftop rainwater harvesting.

2.             Allowing water into ground directly through roadsides drains.

7.             How are clouds  formed?

ANS: Clouds are formed due to process of evaporation  and condensation when air moves up, it gets cooler and cooler. At sufficient height the air become so cool that water vapours present in the air condense. They  form tiny droplets and float in air as clouds.

Q2. Define the following

1. Freezing 2. Melting 3. Evaporation 4. Condensation 5. Precipitation

6. Groundwater 7. Flood 8. Drought 9. Rainwater harvesting 10. Hail