Topsy Turvy – demonstrate air pressure

Materials required

Procedure:

1) Fill the Empty glass bottle to the brim with water. Slow fill it to ther brim so that a convex blulge on the bottles mouth.
2) Tear-off or find a piece of.
3) Place the paper that is a little bigger than the mouth of the bottle over the mouth of the bottle.
4) Gently tap the paper on the bottle mouth & make sure it gets wet and gets sealed with
the bottle's glass mouth
5) Turn the bottle upside-down slowly and steadily. If you had followed the procedure carefully the water inside the bottle will stay intact supported on the paper.

Caution:
- While flipping the bottle, do it over a empty in case…
- Do not touch or try to remove the paper on the mouth of the bottle while the bottle is upside down.
- Turn the bottle slowly and do not shake the bottle while tipped.

Inference:

By all means the water should have pushed the paper and poured down because of gravity. It doesn’t happen because; the air pressure acting upwards is greater than the gravitational force trying to pull the water down. This experiment demonstrates air pressure