Hierarchy classification:

1. top of the aat hierarchies
2. Associated Concepts Facet
3. Associated Concepts (hierarchy name)
4. scientific concepts
5. physical sciences concepts
6. physics concepts
7. [energy and related concepts]
8. energy-related concepts
9. heat-related concepts

Anotations

Scope note:

The ratio of the amount of work performed by a heat engine in one cycle to the amount of energy input required to operate the engine over one cycle. This ratio may be applied to the ability of an object, machine, or structure to maintain temperature parameters measured against the energy expended to control that temperature.