Physics

Efficiency

Ratio of useful output to input energy.

Formula

Formula
η = outputinput · 100

Variables

SymbolDefinitionType & rangeUnitsRole
output useful energy out 0 ≤ output ≤ input J result
input energy supplied input > 0 J result
η efficiency 0 ≤ η ≤ 100 % result

Try it yourself

Interactive calculator
Result

Worked examples

Example 1
Givenuseful output = 750, energy input = 1000
Result75
Example 2
Givenuseful output = 40, energy input = 100
Result40