Make a plastic bottle collapse without touching it! The air does the job for you. You cannot feel air, but it presses against every surface. This is called “air pressure”.
Materials:
1. Ice
2. Funnel
3. Hot and Cold Water
4. Plastic soft drinks bottle
5. Bowl
Procedure:
1. Stand the bottle upright in a bowl. Pour the hot water into it and leave it for a short time.
2. Screw the top on the bottle. Lay the bottle in the bowl and pour ice and cold water over it. Then stand it up.
3. The bottle collapses! As the warm air inside the bottle cools, it exerts less pressure. The air outside is stronger and crushes the bottle.
