1. Balloon Crushing Bottle Experiment
When you place a balloon over the mouth of a bottle and heat the bottle, the air inside the bottle expands and escapes.
When the bottle cools down, the air inside contracts and pressure inside becomes lower.
The higher atmospheric pressure outside pushes the balloon into the bottle, making it look like the balloon is getting crushed.
👉 This shows air pressure can push strongly when inside pressure decreases.
2. Can Crushing Due to Air Pressure
A metal can is heated with some water inside.
The steam produced pushes out most of the air.
When the hot can is suddenly cooled (like dipping it in cold water), the steam condenses and pressure inside drops.
The outside atmospheric pressure becomes much higher and crushes the can instantly.
👉 This proves atmospheric pressure is strong and acts from outside.
3. Water Rising in a Glass With a Candle
Place a candle in a plate filled with water and cover it with a glass.
The candle burns and heats the air inside the glass.
When the candle goes out, the air cools and contracts, reducing pressure inside the glass.
The higher outside pressure pushes water up into the glass.
👉 This shows air pressure differences cause water to rise.
4. Measuring Pressure by Changing Area
If you press your finger on a table, you feel little pressure.
But if the same force is applied using something with a smaller area (like a pointed pen cap), you feel more pressure.
This activity shows that pressure increases when force is applied on a smaller area, and decreases when area increases.
👉 This demonstrates the formula:
Pressure=Force/Area