# How much power is produced if a voltage of 12 V is applied to a circuit with a resistance of 288 Omega?

May 15, 2018

I got $0.5 W$

#### Explanation:

We know that Power is Work/Energy transformed in one second.
In terms of Electricity we know that Power $P$ is:

$P = V I$

this tells us that Voltage, $V$, which is the energy transported per charge ($\frac{E}{q}$) is multiplied by the Current $I$, which is charge passing each second ($\frac{q}{t}$).
So we get:

$P o w e r = V I = \text{Energy"/cancel("Charge")*cancel("Charge")/"Time"="Energy"/"Time}$

we can now use Ohm's Law $V = R I$ that can be written as:

$I = \frac{V}{R}$ and substituted into the Power to get:

$P = V I = V \frac{V}{R} = {V}^{2} / R = {\left(12\right)}^{2} / 288 = 0.5 W$