Pick the best description of energy efficiency? A efficiency is equal to the ratio of energy you put into the energy you get out B efficiency is equal to the ratio of energy you get out to the energy you put in C efficiency is equal to the sum of the energy you put into the energy you get out
The answer is B. Efficiency is equal to the ratio of energy you get out (output) to the energy you put in (input). Say for a basic example you got a converted output of 40W from 50W input, you'll have an efficiency of 80 percent only.
