What you need

• A stick (1m long)
• A lump of clay

Instructions

1. Push a lump of clay about the size of your fist on to the stick 20cm from the end
2. With the clay-end closest to your hand, try balancing the stick
3. Now turn the stick upside down and try balancing it again

Results and Explanation

It's much easier to balance it the second way. The stick rotates slower when the clay is at the top, so there's more time to adjust and keep it balanced. The further the mass is from the centre of rotation (your hand), the slower it rotates.

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.