Question

When both the current and voltage in a circuit are doubled, what happens to resistance and power?

Answer 1

Resistance remains same, but power becomes four times i.e. quadruples.

Explanation:

If current is `I` and voltage is `V`, then resistance `R=V/I` and power is given by `P=V*I`.

As such when both the current and voltage in a circuit are doubled, resistance becomes `R=(2V)/(2I)=V/I` and hence remains same.

However, power becomes `P=2V*2!-4V*I` i.e. power becomes four times.