Question

In $P-V$ diagram shown in figure $ABC$ is a semicircle.The work done in the process $ABC$ is

• A. $4J$
• B. $\frac{-\pi }{2}J$
• C. $\frac{\pi }{2}J$
• D. zero

Answer 1

The correct option is C $\frac{\pi }{2}J$

$\text{Solution}:$

Net work done is positive and area between semicircle which is equal to $\frac{\pi }{2}(2-1)\times \frac{(3-2)}{2}Nm=\frac{\pi }{2}J$.

As the curve is going anti-clockwise, the work done is positive.

$\text{Hence C is the correct option}$