Question

The resistance of a wire is 'R' ohm. If it is melted and stretched to 'n' times its original length, its new resistance will be:-
(a) $\frac{R}{n}$
(b) n²R
(c) $\frac{R}{n^{2}}$
(d) nR

Answer 1

As R=pl/A

Hence then carry out the answer

Answer 2

Electrical resistance in a conductor wire is dependent on it's physical characteristics including it's volume and length.

According to the Ohm's law of resistance,we came to know that if a conductor is stretched n times than it's initial length ,then the ratio of the initial and final resistance will be "n²" .

Then the final resistance will be n²R.

And that's why the correct answer of this question is option b.