Question

Mention the significance of Zeroth law of Thermodynamics.

Answer 1

Zeroth law $-$ If body $A$ is in thermal equilibrium with only $B$ and $C$, then $B$ is in thermal equilibrium with $C$ as well.

Significance $-$ It defines temperature and is basis for $1^{st}$ and $2^{nd}$ law of thermodynamics.