A refrigerator has a coefficient of performance of 6.If the refrigerator absorbs 50 cal of heat from the cold reservoir in each cycle,evaluate the heat expelled into the heat reservoir.

Question

Quizplus · Accepted Answer

Coefficient of performance = Heat absorbed from cold reservoir / Work done = Qc / W
Given coefficient of performance = 6
Heat absorbed from cold reservoir (Qc) = 50 cal
Therefore, Work done (W) = Qc / Coefficient of performance = 50 / 6 = 8.3333 cal
Heat expelled into the heat reservoir = Work done - Heat absorbed from cold reservoir = 8.3333 - 50 = -41.6667 cal
Note that the negative sign indicates that heat is expelled from the refrigerator into the heat reservoir. Since heat cannot be expelled in negative amounts, we take the absolute value and get 41.6667 cal, which is approximately 42 cal. To find the answer choice closest to this value, we choose D, which is 58 cal, the closest value to 42 cal.

A Refrigerator Has a Coefficient of Performance of 6