Question

How much power is produced if a voltage of `12 V` is applied to a circuit with a resistance of `144 Omega`?

Answer 1

`1 "Watt"`

Explanation:

We can use the formulas `P = IV` (`"Power" = "Current" xx "Voltage"`)
and Ohm's Law (`V = IR`; `"Voltage" = "Current" xx "Resistance"`) to find the power from Voltage and Resistance.

In the first equation `P = IV`, we do not have the Current (`I`), so we rearrange Ohm's law into:

`I = V/R`

We substitute this into `P = IV`

`P = V/R xx V`

and we get

`P = V^2/R`

Now we just substitute the values from the question into the formula:

`P = (12V^2)/(144Omega) = 1W`

And we can see that the answer is `1 "Watt ("W")"`