A current of 1.0 mA is flowing through a potentiometer wire of length 4 m and of resistance 40 N. The potential gradient of the potentiometer wire will be:

$10^{-1} V/m$ $10^{-2} V/m$ $10^{-4} V/m$ $10^{-3} V/m$

$10^{-2} V/m$

The correct answer is Option (2) → $10^{-2} V/m$