Current Electricity Question 9
Question 9 - 2024 (27 Jan Shift 2)
Wheatstone bridge principle is used to measure the specific resistance $\left(\mathrm{S}_{1}\right)$ 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 :
(1) $\frac{S_{1}}{4}$
(2) $2 \mathrm{~S}_{1}$
(3) $\frac{S_{1}}{2}$
(4) $S_{1}$
Show Answer
Answer: (4)
Solution:
As specific resistance does not depends on dimension of wire so, it will not change.
