Question

If a 0.75 efficient motor produces 150 W of useful power, what was the input power? *

Answer 1

Answer:

The input power is 200 W

Explanation:

Motor Efficiency

The efficiency of a motor can be calculated as follows:

$\displaystyle \beta=\frac{P_o}{P_i}$

Where:

β   = efficiency

Po = Output power

Pi  = Input power

Solving for Pi:

$\displaystyle P_i=\frac{P_o}{\beta}$

The efficiency is β=0.75 and the output power is Po=150 W, thus the input power is:

$\displaystyle P_i=\frac{150}{0.75}$

$P_i=200 \ W$

The input power is 200 W