We know that air is all around us but we were wondering if air is very strong?
We tested this by using a bottle and a ping pong ball.
If you fill a bottle with water and then put a ping pong ball on top instead of a cap, what do you think will happen if you turn both up-side down.
Will the ping pong ball fall, causing all the water to splash all over the place?
Will the ping pong ball stay where it is and act as a stopper, keeping all the water in the bottle?
The water in the bottle wants to fall to earth (gravity is pulling the water) but the air under the ping pong ball pushes it up against the bottle keeping all the water in the bottle.