At home for 5-11 11-14
What you need
- A clear plastic bottle
- A pen
- A balloon (blow it up a few times beforehand)
- Make a hole in the bottom of the bottle with the pen
- Push the balloon inside and stretch it over the mouth
- Blow up the balloon
- Notice air is coming out of the hole in the bottle
- Cover the hole with your finger and stop blowing
Results and Explanation
The balloon stays inflated! As the balloon expanded, it pushed air out of the bottle. That made the pressure inside the bottle lower than the pressure inside the balloon, so it wasn't strong enough to squeeze the air out.
These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.