What you need
- 5 coins of the same value, each from a different year
- small bag or box
What to do
This is a magic trick to be presented to a group of people who have NOT read these instructions.
- Lay the coins on a table and ask a volunteer to look at the coins. Ask them to confirm that they each have a different year stamped on them.
- Place the coins in the small bag or box and ask the volunteer to select one coin and look at the year on the coin without showing you.
- Ask the volunteer to hold the coin firmly in their hand and think about the year to make sure they remember it. Meanwhile, act as though you are attempting to ‘read their mind’.
- Ask the volunteer to return the coin to the bag or box. 5. Mix up the coins before reaching in to ‘magically’ retrieve the correct (warmest) coin.
What’s happening?
When a metal coin is held in a warm hand, heat energy is transferred from the person’s hand to the coin. Metals are very efficient conductors of heat, so it doesn’t take long for a metal coin to reach the same temperature as a warm hand holding it. The ‘magician’ simply retrieves the warmest coin from the bag.
This trick works more reliably with a child as the volunteer as children tend to have warmer hands than adults.