Current Electricity and Electrical InstrumentHard

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 :-

Options

A.

R/n

B.

n2R

C.

R/n2

D.

nR

Solution

R = ρlA=ρl2volume⇒R∝l2
⇒ R2 = n2R1

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