Question
Physics Question on Thermodynamics
An ideal gas in equilibrium at temperature T expands isothermally to twice its initial volume. If ΔS, ΔU and ΔF denote the changes in its entropy, internal energy and Helmholtz free energy respectively, then
A
ΔS < 0, ΔU > 0, ΔF < 0
B
ΔS > 0, ΔU = 0, ΔF < 0
C
ΔS < 0, ΔU = 0, ΔF > 0
D
ΔS > 0, ΔU > 0, ΔF = 0
Answer
ΔS > 0, ΔU = 0, ΔF < 0
Explanation
Solution
The correct answer is (B) : ΔS > 0, ΔU = 0, ΔF < 0