Q. When gas in a vessel expands its internal energy decreases. The process involved is
A) Isothermal
B) Isobaric
C) Adiabatic
D) Isochoric
Explanation
(c) From, first law of thermodynamics
$dQ = dU + p\ dV$ ------(i)
According to the question when gas expands, its internal energy decreases.
So, from Eq. (i) dQ remains constant
Hence, the process is adiabatic.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.