‘AIR’ is not visible, but can be felt. How do you know that AIR is in your
surroundings? Write 3 experiences about it
Answers
Answer:
1) While walking, we sometimes feel air pushing us, This can be a great example to show the presence of air around us.
2) Leaves during autumn season fly with the wind.
3) Clothes hanged up in the air fly sometimes during high pressure
4) Kites fly in the sky because of the presence of air
There can also be an acitvity demonstrated to show the prescense of air:
For this, take a candle, a glass tumbler and a pan which is filled with some water. Keep the candle upright in the pan and light the candle. Now cover the candle with the glass tumbler. It is observed that the candle extinguishes after some time.
This happens because oxygen in the air inside the glass tumbler is utilised in burning the candle. All the oxygen gets converted into carbon dioxide. Carbon dioxide does not support burning and hence candle stops burning.
Once the candle stops burning, some amount of water is sucked inside the tumbler. This happens because the volume of cabron dioxide is less than the volume of oxygen which was displaced.
It is also seen that a lot of air is still inside the tumbler. A major portion of this air is nothing but nitrogen. Nitrogen too does not support burning.