Page 78 - Viva ICSE Science 4 : E-book
P. 78
ACTIVITY TIME
Air occupies space and has weight
Aim:
To show that air occupies space and has weight
You Need:
Three fl at balloons, a coat hanger
What to Do:
• Take a fl at balloon and blow air into it. The balloon infl ates and becomes big.
Next
• Take a coat hanger. Tie the inflated balloon on one of its sides and a fl at balloon on the
other side to see if they weigh the same.
• Remove the flat balloon and replace it with another infl ated balloon. Now observe what
happens.
Observation:
In the fi rst case, you will observe that the fl at balloon becomes bigger in shape. This happened
because air blown into the balloon occupied all the space that was available to it.
In the second case, you will observe that the hanger tilts towards the side tied with the infl ated
balloon. This is because air has weight and makes the infl ated balloon heavier. While, the
hanger with two infl ated balloons has no such tilt as the weight is equal on both the sides.
Result:
This shows that air occupies space and has weight.
ACTIVITY TIME
Air expands on heating
Aim:
To show that air expands when it gets heated up
You Need:
A fl at balloon, an empty water bottle, two bowls, hot water, cold water
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