The atmospheric pressure
This funny experiment is very easy to make with an adult. You will learn another characteristic of the air around you!
How does it work?
This experiment is about the atmospheric pressure. The air weights something and puts pressure on everything around it, even toward the top. You can't feel it, but air puts pressure on you all the time!
In this experiment, water puts pressure on the carboard, but air puts even more pressure on it.
Preserving jars are hard to open because of the atmospheric pressure. The outside pressure of air is important, and there is no air inside the jar to balance it on both side. When you open the top, you allow air to get inside the jar, and to balance the pressure. Now you can open it!
- A glass
- A piece of cardboard
How to make this experiment?
- Fill up the glass with water.
- Cover it up with the piece of cardboard.
- Ask an adult to maintain the piece of cardboard, and to turn over the glass above a sink or a bassin.
- The piece of cardboard sticks to the glass!