Page 75 - ACTIVE SCIENCE 4 TOC

T he Sun And The Weather

The sun is a huge ball of fire. It causes the change in the weather. The condition
of atmosphere around us at a specific time is called weather. The weather can

be hot, cold, windy, dry or humid. The weather is different everywhere. The place
where you live can be hot, in other places it may be cloudy or snowy. It is also
possible that when you go to school in the morning, it might be sunny but on
your way back home, it can be rainy. The main factors responsible for weather

change are movement of air and change in the form of water. Both the factors are
influenced by the heat of sun.

What Causes Day And Night?

The earth rotates around the sun.
It takes 24 hours to complete one
rotation. The earth’s rotation on its
axis causes day and night. The part

of the earth that faces the sun and
receives light has day, and on the Sun
other hand, the part of the earth that

is away from the sun and does not Day and Night
get light has night.

Why Do We Have Seasons?

There are three main seasons in
Orbit India – winter, summer and

monsoon. The earth revolves
around sun in its own orbit and
takes 365 days and 6 hours to

Sun complete this revolution. An orbit
is a fixed path that one object in
space takes around another. The

part of the earth which faces the
sun has warmer and longer days.
This part has summer season. On

the contrary, the part which is far
Earth Revolving Around the Sun from the sun has cooler and shorter

days. This part has winter season.
Therefore, changes in seasons are caused by the earth’s revolution around the sun.

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