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Take your handkerchief and dip it into water. Now spread your wet
handkerchief in front of a table fan. Be careful! Keep it at a distance from the fan. What do you
observe? Discuss in the class.

Activity 2

Go into a room and switch off the
lights. The room will become dark.
Now observe the light coming from
the hole of a window. What do you
observe? You will see small particles
coming with the light. These are dust
particles. This shows that air also
contains dust particles.

Dust particles in air carry germs. Germs make us ill.

Properties of Air

Let us perform some activities to learn about the properties of air.

Activity 3

Take a deflated ball and put it on a Deflated Ball Ball Filled
weighing machine. Notice the weight. With Air
Now fill the same ball with air and put it
on the same weighing machine. Notice
the weight. Now observe both the
weights. You will notice that the ball
filled with air has more weight. This
shows that air has weight.

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