Question

Define the following: thermal expansion.

Answer 1

1. Thermal expansion: It is one of the effects of heat in which all forms of matter (solid, liquid, and gas) show expansion on heating.
2. On heating, the molecules of matter absorb heat and start vibrating which results in an increase in intermolecular space.
3. Therefore after heating matter expands.
4. For example, when an iron rod is heated its length increase.