Question

What’s the total power in a circuit with a current of 4A and a resistance of 12 ohm?

Answer 1

Power = Current *Voltage  

You already have the current, but not the voltage.  

But you are given resistance, and you know that  

Voltage=Current*Resistance  

Therefore  

V=I*R=4*12=48V  

So you have 48V  

Now you can figure out the Power  

P=I*V=4*48=192W  

Therefore you have 192W.

hope this helps