Efficiency Formulas and the Carnot Cycle

Vocabulary terms and mathematical formulas regarding heat engine efficiency, thermodynamic temperature, and the Coefficient of Performance (COP) as described in the lecture notes.

Efficiency for reversible engines

The measure of performance for engines operating between a high reservoir ($T_H$) and low reservoir ($T_L$), calculated as $Efficiency_{rev} = 1 - \frac{T_L}{T_H}$.

Thermodynamic Temperature

The temperature scale used in efficiency formulas, measured in Kelvin ($K$).

Carnot Heat Engine

The most efficient type of heat engine operating between defined hot and cold reservoirs, defining the maximum achievable efficiency for a reversible engine.

Coefficient of Performance (COP)

A value used to measure the efficiency of refrigerators and heat pumps, defined by the formula $COP = \frac{q_{in}}{W_{in}}$.

Rejection Temperature Limit ($T_L$) and COP

As the low temperature limit decreases, the Coefficient of Performance decreases because more work ($W_{in}$) is required to extract heat from colder bodies.