JEE PHYSICS MCQ: CURRENT ELECTRICITY

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In order to increase the resistance of a given wire of uniform cross-section to four times its value, a fraction of its length is stretched uniformly till the full length of the wire becomes

\frac{3}{2}

times the original length. What is the value of this fraction?

View answer and explanation

Correct option: B

\frac{1}{8}

Option B (

\frac{1}{8}

) is correct because it is the fraction of the wire that needs to be stretched to achieve the desired resistance increase, calculated by solving the equations derived from the length and resistance changes.

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