Question

A thermodynamic process o f one mole ideal gas is shown in the figure. The efficiency of cyclic process $ABCA$ will be

• A. $25\%$
• B. $12.5\%$
• C. $50\%$
• D. $7.7\%$

Answer 1

Answer: (D)

$W = \frac{1}{2}P_{0} V_{0} , T_{A }= T_{0}, T_{B} = 2T_{0}, T_{C}= 4T_{0}$
Heat supplied $Q_{AB} + Q_{BC} = C_{V}T_{0} + C_{P}2T_{0} $
$= \frac{13}{2}RT_{0} = \frac{13}{2} P_{0}V_{0}$
$\therefore $ Efficiency of the cyclic process
$=\frac{\frac{1}{2}P_{0}V_{0}}{\frac{13}{2}P_{0}V_{0}}\times 100 $
$= \frac{1}{3} \times 100 = 7.7 \%$