Thermodynamics Question 51
Question: During an adiabatic expansion of 2 moles of a gas, the change in internal energy was found -50J. The work done during the process is
[Pb. PET 1996]
Options:
A) $ 350\times {{4}^{0.4}}K $
B) $ 300\times {{4}^{0.4}} $ K
C) $ 150\times {{4}^{0.4}} $ K
D) None of these
Show Answer
Answer:
Correct Answer: B
Solution:
For adiabatic change $ T{{V}^{\gamma -1}} $ = constant
Therefore $ \frac{T _{2}}{T _{1}}={{( \frac{V _{1}}{V _{2}} )}^{\gamma -1}} $
Therefore $ T _{2}={{( \frac{V _{1}}{V _{2}} )}^{\gamma -1}}\times T _{1} $
Therefore $ T _{2}={{( \frac{V}{V/4} )}^{1.4-1}}\times 300 $
$ =300\times {{(4)}^{0.4}}K $
