How much power is produced if a voltage of #4 V# is applied to a circuit with a resistance of #27 Omega#?
Probably not a lot more explanation needed. We are given a voltage
We do know a way to find the current, given the voltage and the resistance: Ohm's Law :
We could calculate the current and then substitute that into the expression for the power, but I decided to combine the equations instead:
Then it's just a matter of substituting in the values we have and we know the power produced by the circuit.