Question
Describe an experiment to show that solids expand on heating and contract on cooling.
Answer
Experiment: Cubic expansion of an iron ball on heating
Take an iron ball and a ring such that the ball just passes through the ring as shown in fig (a). Now, heat the ball and try to pass it through the ring. You will find that the ball does not pass through the ring fig (b). Why is this so?
When the ball is heated, it expands and its size increases. After some time, when the ball coos, it will again pass through the ring. This experiment shows that solids expand on heating and contract on cooling.
