Question

Why heat produced by the conductor is directly proportional to square of the current​

Answer 1

Answer:

Explanation:

in electricity,

V=W/q (work done per each charge to separate it from other charges and keep somewhere.)

I=q/t (number of charges flowing in unit time when they are allowed to flow.

P=W/t=I*V (total work done in unit time)

So energy is E=I*V*t=I^2Rt=V^2t/R

( since V=IR, or I=V/R)

For a fixed power P=VI=Constant.

Ie, if V increases, I reduces and if V reduces, I increases.

Ie, Energy of 10 electrons with each 10Volt potential is equal to that of 5 electrons with 20Volt potential each.

But for effective work to be done, Current(electron flow) must be high, rather than Potential V (energy of each electron). This is due to the limitation on wire resistance.

However good conductor you may take, the number of electrons that it allow reduces with its reduction in area of cross section. So less the area of cross section, more is the resistance.

That is why, during energy transmission , we step up to reduce heating losses.

Usually power is produces at 33KV potential. Let us say some 100Amp current is generated at 33KV. Ie, for name sake 100 electrons with 33KV potential energy. But for transmission, the wires may not allow more number of electrons. Rather they allow less number of electrons each with high energy. So they step up. And make it 330KV and 10Amp. (E xd closing losses.) Ie, the energy of 100 electrons is redistributed to 10 electrons each at 330KV potential energy.

So Finally the heat energy produced by current is given by Q=I^2Rt rather than V^2t/R.