Page 159 - Volt Elevate The World Around Us Book 4

Some examples of evaporation in our daily life are given below.

y Sweat from our body dries up due to evaporation.
y Wet clothes dry when we put them in the sun and the water evaporates from them.

y Salt is also extracted from seawater using the process of evaporation. Dykes are
made on the shore to prevent seawater from flowing back into the sea. These areas
with dykes are called salt pans. The water in these pans gradually evaporates leaving
a layer of salt behind. This is the salt we eat after it is refined in the factories.

Condensation

On cooling, water vapour changes back to droplets of water. This is called condensation.
When we boil water in a kettle, we can see steam (water vapour) coming out from its
nozzle.
If we place a plate in front of the nozzle, we will find water droplets
on the surface of the plate facing the steam. This is condensation.

Dew drops on leaves in winter is an example of condensation in
our daily life.
condensation of steam
Water Cycle

Water is circulated continuously in nature in the form of water cycle. During this
circulation, it keeps changing its form.

Water evaporates from rivers, lakes and other water bodies because of the heat of the
sun. Some of this water changes into water vapour and rises in the sky. As it goes higher,
it comes in contact with cold air and condenses to form clouds. As more and more drops
join the clouds, they become heavy and cannot hold water any longer. This water from
the clouds falls on the ground in the form of rain, hail, snow and sleet. This is precipitation.

Water reaches water bodies on the earth due to precipitation and again evaporates. This
water cycle goes on endlessly in nature.

Water evaporates to form
vapour and they rise.

Water gets heated up due to Water vapour cools down
the heat of the sun. and condenses to form
clouds.
Water precipitates in the
form of rain or snow.
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