Question

When the potential diference across resistive conductor of resistance R obeying ohm law is doubled then the generation of heat is

Answer 1

According to Ohm’s law V=IR

Hence when nothing changed Io=VR

When potential difference is doubled and resistance is halved, then the current flowing is given by

I′=V′R′=2×VR2=4VR=4I0

Hence current will become 4 times the original value.

Answer 2

If the potential difference is doubles then the heating also increases.

It could be understood by the following equations.

As per Joule's Law of Heating

        H= I^2Rt   ----1.

For which,

• H = heat
• I   = current

• R = Resistance

• t = time  

Also according to ohm's law

          V = IR  

          I  = V/R   -------- 2.

substituting equation 2. to 1.

we get,

        H = (V^2t)/R

Hence the heat produced is also increased as per the increase in voltage.

Hope it helps : )