All Problems

Second law of thermodynamics, entropy

Problem 2.147

A working substance goes through a cycle within which the absolute temperature varies \(n\) -fold, and the shape of the cycle is shown in (a) Fig. \(2.4 a ;\) (b) Fig. \(2.4 b\), where \(T\) is the absolute temperature, and \(S\) the entropy. Find the efficiency of each cycle.

Reveal Answer
 (a) η=(n1)/2n (b) η=(n1)/(n+1)\text { (a) } \eta=(n-1) / 2 n\text { (b) } \eta=(n-1)/(n+1)