Question
Question: An ideal gas is taken through the cycle A ® B ® C ®A , as shown in the figure. If the net heat suppl...
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–
A
–5 J
B
– 10 J
C
– 15 J
D
– 20 J
Answer
–5 J
Explanation
Solution
DWAB = PDV = (10) (2 – 1) = 10 J
DWBC = 0
From first law of thermodynamics
DQ = DW + DU
DU = 0 (process ABCA is cyclic)
\ DQ = DWAB + DWBC + DWCA
\ DWCA = DQ – DWAB – DWBC = 5 – 10 – 0 = – 5 J