# If a current of 5 A passing through a circuit generates 45 W of power, what is the resistance of the circuit?

$1.8 \setminus \Omega$

#### Explanation:

Equations you can work with electrical work are

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

Given in the problem are:
$I = 5 A$
$P = 45 W$

Make use of the equation $P = {I}^{2} R$ where $R = \frac{P}{I} ^ 2$

Therefore,
$R = \frac{45 W}{5 A} ^ 2 = 1.8 \setminus \Omega$