What you need

• A table
• A ruler
• A newspaper

Instructions

1. Lay the ruler on the table so about a third of it hangs over the edge
2. Carefully lay a single sheet of newspaper flat on the table and over ruler
3. Hit the end of the ruler with your hand – the ruler stays where it is!
4. What happens if you try again, but this time with the sheet of newspaper folded up?

Results and Explanation

The flat sheet of newspaper has a large enough area so that the downward force of the atmosphere counters the upward force from the ruler. But the folded-up newspaper has a much smaller surface area, so doesn’t stop the ruler from going flying when it’s hit.

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.