Question

How would you demonstrate the presence of atmospheric pressure?

Answer 1

To show the presence of atmospheric pressure, you need a glass tumbler, a stiff cardboard and water. Take the tumbler and fill it with water such that it is full till the brim. Cover it with a cardboard piece. Then place your hand over the cardboard piece on the tumbler and quickly invert it. Now, slowly, remove your hand while supporting the cardboard piece. It is observed that the cardboard piece does not fall. This proves that there is atmospheric pressure that provides enough force to support the weight of the water in the tumbler.