Q.
What is the nature of change in internal energy in the following three thermodynamical processes shown in figure?
A) $\mathrm{\Delta}U$ is positive in all the three cases
B) $\mathrm{\Delta}U$ is negative in all the three cases
C) $\mathrm{\Delta}U$ is positive for (i), negative for (ii), zero for (iii)
D) $\mathrm{\Delta}U = 0$, in all the cases
Explanation
(d) As indicator diagram if all the three cases are closed curves, representing cyclic changes, therefore, $U =$ const and $\mathrm{\Delta}U = 0$ in all the cases
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.