Crush with Air

The purpose of this experiment is tomake aplastic bottle collapse without touching it. Theair does the job for you.

You will need:

1. Thin card

2. Two cups, one for cold water and one for hot water

3. Plastic bottle with top

4. A small basin

Experiment Steps:

1. Use the thin card to make a funnel.

2. Stand the bottle upright in the basin. Pour the hotwater into the bottlethrough the funnel. Leave it on the table for a short time.

3. Get some water in your small basin. Put some ice into your cold water cup.

4. Screw the top on the bottle. Lay the bottle inthe basin and pour cold water over it .Thenstand it up.

5. As the warm air inside the bottle cools, itgives less pressure. The pressure of the air outside is stronger and crushes the bottle.

Experiment Interpretation:

You cannot feelair,but it presses against every surface. Thisis called “air pressure”. When we pour cold water over the hot plastic bottle, the warm air inside the bottle cools, itexerts less pressure. The pressure of the air outside is stronger and crushes the bottle.

Knowledge-Air Support

A bicycle pump forces more and more air into the inner tube of a tyre. The air pushes outwards on the walls of the tube. It pushes so hard that it can support the weight of both the bicycle and the rider.