# Thermal Efficiency of an air conditioner

## Homework Statement

The thermal efficiency of a refrigerator is determined by the coefficient of performance , which is defined as the ratio of the amount of heat removed to the input of mechanical work needed for operation, or K=Q_c/W_in

An air conditioner operates exactly as a refrigerator; it removes heat from a cold place (a bedroom, for example) and conveys it to a warmer place (usually the outside). Quantities of practical importance in understanding the efficiency of air conditioners are the rate of heat removal and the electric power input to the unit (i.e., the electric energy consumed per unit time). Find an expression for the coefficient of performance of an air conditioner that has a rate of heat removal H and a power consumption P . <!-- that removes an amount of heat Q_c in time , given its rate of heat removal H and the power input P=W_in/t needed for operation. --> express in terms of H and P