Physics-
General
Easy
Question
An ideal gas is taken through the cycle A ® B ® C ® A, as shown in the figure. If the net heat supplied to the gas in the cycle is 5 J, the work done by the gas in the process C → A is
- – 5 J
- – 10 J
- – 15 J
- – 20 J
The correct answer is: – 5 J
For cyclic process. Total work done 
DWAB = PDV = 10(2 – (a) = 10J and DWBC =0
(as V = constant)
From FLOT, DQ = DU + DW
DU = 0 (Process ABCA is cyclic)
ÞDQ = DWAB + DWBC + DWCA
Þ 5 = 10 + 0 + DWCAÞ DWCA = – 5 J
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