Efficiency Formula
η = E_out / E_in
What it means
Efficiency is the ratio of useful output energy to total input energy, often given as a percentage.
Variables
| Symbol | Quantity | SI unit |
|---|---|---|
η | efficiency | — |
E_out | useful energy | J |
E_in | input energy | J |
Worked example
Given E_out = 80 J, E_in = 100 J, solve for η:
η = 0.8