Explain Ball and ring experiment

1. A metal ball is heated and then passed through a metal ring. If the ball has expanded due to heating, it will not pass through the ring.
2. If the ball is cooled down, it contracts. When cooled, it will then pass through the ring.
3. Conversely, if the ring is heated and the ball is at room temperature, the ball will not pass through the expanded ring.

This experiment shows that solids expand when heated and contract when cooled.