Question 435: Thermodynamics & KTG

Question

An engine operates by taking n moles of an ideal gas through the cycle ABCDA shown in figure. The thermal efficiency of the engine is :
(Take C
v
= 1.5 R, where R is gas constant)
![](https://app-content.cdn.examgoal.net/fly/@width/image/1l83ny4qs/b2c2ec7d-be6d-49e7-8ede-46914f3fa629/5a155440-354b-11ed-8c5c-f3f0850e6b94/file-1l83ny4qt.png?format=png)

Accepted Answer

Work done by engine = area under closed curve = P
0
V
0
According to the principle of calorimetry,
Heat given to the system,
Q = Q
AB
+ Q
BC
= nC
v
$\Delta $T
AB
+ nC
p
$\Delta $T
BC
= ${3 \over 2}$ (nR T
B
$-$ nRT
A
) + ${5 \over 2}$ (nRT
c
+ nRT
B
)
= ${3 \over 2}$ (2P
0
V
0
$-$ P
0
V
0
) + ${5 \over 2}$ (4P
0
V
0
$-$ 2P
0
V
0
)
= ${13 \over 2}$ P
0
V
0
$	herefore\,\,\,$ Thermal efficiency
= ${W \over Q}$ = ${{{P_0}\,{V_0}} \over {{{13} \over 2}{P_0}{V_0}}}$ = ${2 \over {13}}$ = 0.15

Answer

0.24

Answer

0.15

Answer

0.32

Answer

0.08

Thermodynamics & KTG

An engine operates by taking n moles of an ideal gas through the cycle ABCDA shown in figure. The thermal efficiency of the engine is : (Take C v = 1.5 R, where R is gas constant)

Choose the correct answer: