Question 11 Mark
A system goes from P to Q by two different paths in the P-V diagram as shown in Fig. Heat given to the system in path 1 is 1000J. The work done by the system along path 1 is more than path 2 by 100J. What is the heat exchanged by the system in path 2?
Answer
View full question & answer→For path (1) Q1 = +1000J W.D =W1 - W2=100 W1 = WD through path 1 W2 = WD through path 2
$\therefore$ W2 = W1 - 100 As change in internal energy by path 1 and 2 are same
$\Delta\text{U}=\text{Q}_{1}-\text{W}_{1}=\text{Q}_{2}-\text{W}_{2}$
1000 - W1 = Q2 - (W1 - 100) 1000 = Q2 + 100 Q2 = 900J.