# A charge of 6 C passes through a circuit every 3 s. If the circuit can generate 36 W of power, what is the circuit's resistance?

Apr 15, 2017

The resistance is $= 9 \Omega$

#### Explanation:

The charge and the the current are related by the equation

$I = \frac{Q}{t}$

$I = \frac{6}{3} = 2 A$

We need the equation

$U = R I$

and

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

Therefore,

$R = \frac{P}{I} ^ 2 = \frac{36}{2} ^ 2 = 9 \Omega$