Question

A given mass of gas expands from state A to state B by three paths 1, 2 and 3 as shown in the figure

If $w_{1},w_{2}$ and $w_{3}$ respectively are be the works done by the gas along three paths, then

• A. $w_{1}>w_{2}>w_{3}$
• B. $w_{1} < w_{2} < w_{3}$
• C. $w_{1}=w_{2}=w_{3}$
• D. $w_{1} < w_{2};w_{1}>w_{3}$

Answer 1

Answer: (B)

Work is equal to area under $P-V$ graph (when P is plotted along y-axis). As area under graph 3 is maximum and area under graph 1 is minimum, so $w_{3}$ is maximum and $w_{1}$ is minimum.
So $w_{1} < w_{2} < w_{3}$