Thermodynamics Question 221
Question: A cylinder fitted with a piston contains 0.2 moles of air at temperature 27°C. The piston is pushed so slowly that the air within the cylinder remains in thermal equilibrium with the surroundings. Find the approximate work done by the system if the final volume is twice the initial volume
[BHU (Med.) 2000]
Options:
A) 543 J
B) 345 J
C) 453 J
D) 600 J
Show Answer
Answer:
Correct Answer: B
Solution:
$ W=\mu RT{\log _{e}}( \frac{V _{2}}{V _{1}} ) $
$ =0.2\times 8.3\times {\log _{e}}2\times (27+273) $
$ =0.2\times 8.3\times 300\times 0.693=345J $