Wheatstone bridge principle is used to measure the specific resistance \( (S_1) \) of a given wire, having length \( L \), radius \( r \). If \( X \) is the resistance of the 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: