What is volume expansion? Give the definition and unit of the coefficient of volume expansion.

(N/A) Volume expansion is the increase in the volume of a substance due to an increase in its temperature. When a solid,liquid,or gas is heated,its molecules vibrate more vigorously,causing the material to expand in all three dimensions.
The coefficient of volume expansion $(\gamma)$ is defined as the fractional change in volume per unit change in temperature.
Mathematically,it is expressed as: $\gamma = \frac{1}{V} \frac{\Delta V}{\Delta T}$,where $\Delta V$ is the change in volume,$V$ is the original volume,and $\Delta T$ is the change in temperature.
The $SI$ unit of the coefficient of volume expansion is per Kelvin $(K^{-1})$ or per degree Celsius $(^{\circ}C^{-1})$.