Wheatstone bridge principle is used to measure the specific resistance $\left(S_1\right)$ of given wire, having length $L$, radius $r$. If $X$ is the resistance of wire, then specific resistance is: $S_1=X\left(\frac{\pi r^2}{L}\right)$. If the length of the wire gets doubled then the value of specific resistance will be :
A $\frac{S_1}{4}$
B$2 \mathrm{~S}_1$
C $\frac{S_1}{2}$
D $S_1$
JEE MAIN 2024, Diffcult
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D $S_1$
d As specific resistance does not depends on dimension of wire so, it will not change.
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