Q. Which of the following is correct option for free expansion of an ideal gas under adiabatic condition?
A) q = 0, ΔT < 0, w ≠ 0
B) q = 0, ΔT ≠ 0, w = 0
C) q ≠ 0, ΔT = 0, w = 0
D) q = 0, ΔT = 0, w = 0
Explanation
[Solution from source] In free expansion into vacuum, no work is done (w = 0) and in adiabatic conditions q = 0. Thus ΔU = 0, and for an ideal gas U depends only on T, so ΔT = 0 as well. A temperature drop would occur only for a real gas or reversible adiabatic expansion. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.