Question

A microwave oven running at 70 % efficiency delivers 950 W of energy per second to the interior. Part A Find the power drawn from the source. Express your answer using two significant figures.

Answer 1

Answer:

$P_i\approx1.4\times 10^3\ W$

Explanation:

Given:

• power output of the oven, $P_o=950\ W$

• efficiency of the oven, $\eta=70\%$

We know that the efficiency is given as:

$\eta=\frac{P_o}{P_i}$

where:

$P_i=$ power taken from the source as input to the oven

$0.7=\frac{950}{P_i}$

$P_i=\frac{950}{0.7}$

$P_i=1357.1429\ W$

$P_i\approx1.4\times 10^3\ W$