Question

How do you calculate the efficiency of a simple machine?

Answer 1

Efficiency is defined as the ratio of the power output to the power input.
`eta = (P_(out))/(P_( i n ))`.

Since power is the rate of doing work and the 2 powers occur for the same time while the machine operates, we may also then write efficiency as the ratio of the energy output to the energy input.
`eta = (W_(out))/(W_(i n))`