Question

If $W_{ABC}$ is the work done in process A $\to$ B $\to$ C and $W_{DEF}$ is work done in process D $\to$ E $\to$ F as shown in the figure, then

• A. $|W_{DEF}|>|W_{ABC}|$
• B. $|W_{DEF}|<|W_{ABC}|$
• C. $|W_{DEF}|=|W_{ABC}|$
• D. $|W_{DEF}|=-|W_{ABC}|$

Answer 1

The correct option is C $|W_{DEF}|=|W_{ABC}|$

Work done by a gas in a process is:
from the PV diagram is the area enclosed by the loop
As we can see both loops ABC and DEF have the same area enclosed.
Hence $|W_{ABC}|=|W_{DEF}|$
However the magnitude are opposite.
Option C is correct.