JEE PHYSICS MCQ: CURRENT ELECTRICITY

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Application +4 | -1

A wire of resistance

R

is elongated

n -

fold to make a new uniform wire. The resistance of new wire

View answer and explanation

Correct option: B

{n^2}R

Option B (

{n^2}R

) is correct because when a wire is elongated n-fold, its length increases by a factor of n and its area decreases by a factor of n, resulting in the resistance increasing by a factor of n².

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