# A charge of 40 C passes through a circuit every 8 s. If the circuit can generate 35 W of power, what is the circuit's resistance?

Jan 14, 2017

I got $1.4 \Omega$

#### Explanation:

You can evaluate the current as:
$I = \frac{Q}{t} = \frac{40}{8} = 5 A$

Power can be written as: $P = V I$

Using Ohm's Law: $V = R I$ we write:

$P = {I}^{2} R$

Rearranging:

$R = \frac{P}{I} ^ 2 = \frac{35}{25} = 1.4 \Omega$