Ans. As more and more water droplets gathers, clouds gets thicker, denser and less transparent. Thus, rain clouds look grey in color.
Ans. Water that we get from taps is drawn from a lake or a river or a well. It is then supplied through a network of pipes.
Ans. Sea water is not fit for drinking because it has many salts dissolved in it which is not good for human body.
Ans. Evaporation takes place from all open surfaces after the rains and water vapors gets continuously added to air. Thus, water disappears.
Ans. Water disappears first from the plate kept in sunlight because in sunlight, evaporation takes place faster.
Ans. If we do not have easy access to water for a long period of time then we would not able to cook, clean utensils, wash clothes or bathe.
Ans. The two main natural sources of water are:
1. Surface water – It includes rain water, river and lake water and sea water.
2. Underground water
Ans. The rainwater fills up the lakes and ponds. A part of the rainwater gets absorbed by the ground. Some of this water is brought back to the air by the process of evaporation and transpiration.
Ans. Without adequate water, photosynthesis in plants are greatly reduced which affects the plants growth adversely. After many weeks of such condition, plants die out.
Ans. A part of the rainwater gets absorbed by the ground and seems to disappear in the soil. This water available beneath the surface of the earth is called ground water.
Ans. We need water for many activities such as for drinking, bathing, brushing teeth, washing utensils, washing clothes, for toilet purpose, for cleaning floor etc.
Ans. First shower of rain water is not pure because while coming down through the air, the first showers collect dust particles, germs, bacteria and dissolve some of the gases which are present in the atmosphere.
Ans. During the daytime air in surrounding gets heated. This warm air provides heat for evaporation of water in the shade. Thus, water disappears from the bowl kept in the shade.
Ans. The cold surface of the glass containing ice cools the air around it, and the water vapor of the air condenses on the surface of the glass. So, drops of water appear on outer surface of the glass containing ice.
Ans. When the air moves up, it gets cooler and cooler. At sufficient heights, the air becomes so cool that the water vapor present in it condenses to form tiny drops of water called droplets. It is these tiny droplets that remain floating in air and appear to us as clouds.
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