Written by the Fiveable Content Team โข Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examโขWritten by the Fiveable Content Team โข Last updated September 2025
Definition
Heat engines are devices that convert thermal energy into mechanical work, typically by allowing heat to flow from a high-temperature region to a low-temperature region.
While heat engines convert thermal energy into useful work, heat pumps transfer thermal energy against its natural flow for heating or cooling purposes.
Efficiency measures how effectively a heat engine converts thermal energy into useful work. It is calculated as the ratio of output work to input heat.