A heat engine receives 1 kW of heat transfer at 1200 K and gives out 600 W as work, with the rest as heat transfer to the ambient at 300 K. The second-law efficiency of the engine is:

A heat engine receives 1 kW of heat transfer at 1200 K and gives out 6

1.	A heat engine receives 1 kW of heat transfer at 1200 K and gives out 600 W as work, with the rest as heat transfer to the ambient at 300 K. The second-law efficiency of the engine is:
A.	70%
B.	90%
C.	80%
D.	60%
Answer» D. 60%

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A heat engine receives 1 kW of heat transfer at 1200 K and gives out 600 W as work, with the rest as heat transfer to the ambient at 300 K. The second-law efficiency of the engine is:

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