Two wires of same material have length $L$ and $2L $ and cross-sectional areas $4A$ and $A$ respectively. The ratio of their specific resistance would be
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(d) Specific resistance doesn’t depend upon length and area.
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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?
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