Define heat capacity and write its $SI$ unit.

(N/A) Heat capacity is defined as the amount of heat energy required to raise the temperature of a given substance by $1 \ K$ (or $1 \ ^\circ C$).
Mathematically,it is given by $C = \frac{dQ}{dT}$,where $dQ$ is the heat supplied and $dT$ is the change in temperature.
The $SI$ unit of heat capacity is $\text{joule per kelvin}$ ($J/K$ or $J \cdot K^{-1}$).