Suppose a heat engine is connected to two energy reservoirs, one a pool of molten aluminum at 660°c and the other a block ofsolid mercury at -38.9°c. the engine runs by freezing 3.00 g ofaluminum and melting 45.0 g of mercury during each cycle. thelatent heat of fusion of aluminum is 3.97 105 j/kg, and thatof mercury is 1.18 104 j/kg.
(a) what is the efficiency of this engine?
%
(b) how does the efficiency compare with that of a carnotengine?
%

a)

b)

Explanation:

Given:

a)

Heat absorbed by the engine:

Heat rejected by the engine:

Now the efficiency of the engine:

b)

Now the Carnot efficiency of the engine:

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