# A charge of 18 C passes through a circuit every 2 s. If the circuit can generate 24 W of power, what is the circuit's resistance?

Jun 10, 2017

The resistance is $= 0.296 \Omega$

#### Explanation:

The charge is related to the time and the current by the

$Q = I t$^2=

The charge is $Q = 18 C$

The time is $t = 2 s$

The current is $I = \frac{Q}{t} = \frac{18}{2} = 9 A$

The power is

$P = U I$

But Ohm's Law states that

$U = R I$

So,

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

Therefore,

$R = \frac{P}{I} ^ 2 = \frac{24}{9} ^ 2 = 0.296 \Omega$