Which of the following is a reversed heat engine?

Which of the following is a reversed heat engine?

Options:

a. Heat pump
b. Refrigerator
c. Both a. and b.
d. none of the above

Correct Answer: c. Both a. and b.

Explanation

In a Carnot heat engine all the processes are reversible. It is possible to reverse the processes in the heat engine individually. When a process is reversed, all the energy transfer associated with the process is reversed but the magnitude of the energy remains same. Heat engine absorbs heat from high temperature reservoir and produces work with the rejection of some amount of heat. If this process is reversed, the reversed heat engine takes heat from low temperature reservoir and rejects heat to a high temperature reservoir with external work is done on the system. This is the called as a heat pump or a refrigerator.