Answer:
The Carnot cycle is a theoretical cycle that is used to determine the maximum possible efficiency of a heat engine. However, it is not used in practical applications because it is not a realistic model of how actual engines operate. In practice, real engines experience friction and other inefficiencies that prevent them from achieving the theoretical efficiency of the Carnot cycle. Additionally, the Carnot cycle only applies to reversible processes, which are not possible in practice.
Step-by-step explanation: