A 10-kg copper bar is heated from 40ºC to 200ºC by heat from a reservoir maintained at 400ºC. The entropy generated is nearest:

A) 0.68 kJ/K
B) 0.86 kJ/K
C) 1.18 kJ/K
D) 1.78 kJ/K


A) 0.68 kJ/K

The entropy increase of the copper bar is



The heat transfer to the copper from the reservoir isQ = mC?T =10×0.39×(200 ? 40) = 624 kJ. Finally, the entropy change of the reservoir is

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