Q. In an adiabatic expansion of a gas initial and final temperatures are $T_{1}$ and $T_{2}$ respectively, then the change in internal energy of the gas is
A) $\frac{R}{\gamma - 1}(T_{2} - T_{1})$
B) $\frac{R}{\gamma - 1}(T_{1} - T_{2})$
C) $R(T_{1} - T_{2})$
D) Zero
Explanation
(a) $\mathrm{\Delta}U = - \mathrm{\Delta}W = - \frac{R\left( T_{1} - T_{2} \right)}{(\gamma - 1)} = \frac{R(T_{2} - T_{1})}{\gamma - 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.