Thermodynamics Question 61
Question: In an isobaric process, the ratio of heat supplied to the system $ (dQ) $ and work done by the system $ (dW) $ for diatomic gas is
[AFMC 2002]
Options:
A) 1 : 1
B) 7 : 2
C) 7 : 5
D) 5 : 7
Show Answer
Answer:
Correct Answer: B
Solution:
$ -\frac{dQ}{dW}=\frac{dQ}{dQ-dE} $ ; $ dE=dW+dQ $ ; $ -dW=dQ-dE $
$ =\frac{nc _{p}dT}{nc _{p}dT-nc _{v}dT} $
$ =\frac{c _{p}}{(c _{p}-c _{v})} $
$ =\frac{7R}{2R} $ {for diatomic of gas $ c _{p}=\frac{7R}{2} $ }
