Heat of 1000 kJ is supplied to a heat engine from a reservoir at 1000 K, and it rejects waste heat to a river at 300 K. The engine’s work output is 400 kJ. Its efficiency is:

Heat of 1000 kJ is supplied to a heat engine from a reservoir at 1000

1.	Heat of 1000 kJ is supplied to a heat engine from a reservoir at 1000 K, and it rejects waste heat to a river at 300 K. The engine’s work output is 400 kJ. Its efficiency is:
A.	57.14%
B.	65%
C.	0.30%
D.	40%
Answer» E.

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Heat of 1000 kJ is supplied to a heat engine from a reservoir at 1000 K, and it rejects waste heat to a river at 300 K. The engine’s work output is 400 kJ. Its efficiency is:

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