Question

Why do refrigerators, air conditioners, and heat pumps operate most cost-effectively for cycles with a small difference between Th and Tc? (Note that the temperatures of the cycle employed are crucial to its COP.)

a) Larger temperature differences cause increased energy losses
b) Smaller temperature differences reduce compressor workload
c) Cost-effectiveness is unrelated to temperature differences
d) Larger differences lead to more efficient heat exchange

Answer 1

Refrigerators, air conditioners, and heat pumps operate most cost-effectively with smaller temperature differences between Th and To because it reduces the compressor workload.

Step-by-step explanation:

Refrigerators, air conditioners, and heat pumps operate most cost-effectively for cycles with a small difference between Th (high temperature) and To (low temperature) because smaller temperature differences reduce the compressor workload. Refrigerators, air conditioners, and heat pumps operate most cost-effectively with smaller temperature differences between Th and To because it reduces the compressor workload.

The performance of these systems is measured by the Coefficient of Performance (COP), which is the ratio of heat transferred from the cold environment to the work input required. A smaller temperature difference leads to a higher COP, indicating higher cost-effectiveness.