Question

Calculate the power of a 2057 Ω night light plugged into a 120 V source.

Answer 1

Lets write the data down:

R = 2057 Ω

V = 120 V

The power of the night light is given by:

$P=\frac{V^2}{R}$

Plug in the data in the formula:

$\begin{gathered} P=\frac{120^2}{2057} \\ P=\frac{14,400}{2057} \\ P\approx7.0W \end{gathered}$

The power of the night light is 7.0 W.