Q.

A thermodynamic system undergoes cyclic process ABCDA as shown in figure. The work done by the system in the cycle is              [2014]


 

1 P0V0  
2 2P0V0  
3 P0V02  
4 zero  

Ans.

(4)

In a cyclic process work done is equal to the area under the cycle and is positive if the cycle is clockwise and negative if the cycle is anticlockwise.

As it is clear from figure,

WAEDA=+area of AED=+12P0V0

WBCEB=-area of BCE=-12P0V0

The net work done by the system is

          Wnet=WAEDA+WBCEB=+12P0V0-12P0V0=zero