What You Need:
- 2-liter plastic soda bottle
- A quarter
- Place the empty uncapped bottle in the freezer for 10 minutes.
- Dip the coin in water.
- Remove the bottle from the freezer and immediately place the wet coin on the top of the open bottle.
- Wait and watch the coin move! As it moves, it will make a clickety-clackety noise.
When removed from the freezer, the cold air inside the bottle expands and tries to rush out of the bottle. This air flow causes the coin to move!