Question

For the cyclic process in the figure , which of the following is(are) correct :

• A. $w_{AB}=0$ and $w_{BC}<0$
• B. $w_{BC}>0$ and $w_{CA}>0$
• C. $w_{cyclic}>0$
• D. $w_{BC}<0$ and $w_{CA}>0$

Answer 1

Answer: (A), (C), (D)

$w_{BC}<0$ and $w_{CA}>0$

The process AB is isochoric and hence work done is zero. In the process BC volume increases and therefore work done in negative. In process CA volume decreases and hence work is positive. Now, since area under CA> BC , more work is done during compression (work done on the system) and hence work done in the overall cyclic process is positive.