Asystem goes from P to Q by two different paths in the P -V diagram as shown in figure. Heat given to the system in path 1 is 1000 J. The work done by the system along path 1 is more than path 2 by 100 J. What is the heat exchanged by the system in path 2 ?

Asystem goes from P to Q by two different paths in the P -V diagram as

1.	Asystem goes from P to Q by two different paths in the P -V diagram as shown in figure. Heat given to the system in path 1 is 1000 J. The work done by the system along path 1 is more than path 2 by 100 J. What is the heat exchanged by the system in path 2 ?
Answer» SOLUTION :For path 1: Heat GIVEN `Q_1`=+1000 J Work done = `W_1` For path 2: Work done `W_2=W_1-100J` Heat given `Q_2`= ? As CHANGE in internal energy between TWO states for different path is same. `therefore DeltaU=Q_1-W_1=Q_2-W_2` `therefore 1000-W_1=Q_2-(W_1-100)` `therefore Q_2=1000-W_1+W_1-100` `therefore Q_2`=900 J