Calculate efficiency using useful energy output divided by total energy input.

Efficiency is a measure of how effectively energy is converted from one form to another. It can be calculated by dividing the useful energy output by the total energy input. This ratio indicates how much of the input energy is transformed into useful work, with the remainder often dissipated as wasted energy. Understanding efficiency is crucial in optimizing energy use in various systems, as it highlights areas where energy losses occur and helps in designing more effective energy transfer processes.