Question

Thermodynamic variables —

Answer 1

Thermodynamic Variables : These are macroscopic physical quantities like pressure $(P)$, volume $(V)$ and temperature $(T)$ etc. which are used to describe the state of the system.

The relation between these variables is called equation of state. Heat and work are not thermodynamic variables. Thermodynamic variables are of two kinds, extensive and intensive.

Internal energy $U$, volume $V$, total mass $M$ are extensive variables. Pressure $P$, temperature $T$ and density $\rho$ are intensive variables.