A thermodynamic system undergoes a cyclic process as shown in figure. The cycle consists of two closed loops, loop I and loop II. (a) Over one complete cycle, does the system do positive or negative work? (b) In each of loops I and II, is the net work done by the system positive or negative? (c) Over one complete cycle, does heat flow into or out of the system? (d) In each of loops I and II, does heat flow into or out of the system?

Answer

A, B, C, D

Explanation

(a) `W_I=+ve` (as cycle is clockwise)
`W_(II)=-ve` (as cycle is anti-clockwise)
But,
`|W_1|gt|W_(II)|`
`:.` `W_(n et)=+ve`
(c) `Q_(n et)=W_(n et)=+ve`
(d) In loop-I,
`Q_1=W_I=+ve`
In loop-II,
`Q_(II)=W_(II)=-ve`