Question

To increase the sensitivity of a potentiometer:

• A. the cross-section area of its wire will have to be increased
• B. current in its wire will have to be decreased
• C. current in its wire will have to be increased
• D. length of its wire will have to be increased

Hint:

Sensitivity \(\propto\) potential gradient \(= \frac{V}{L}\). Increasing current raises the potential drop across the wire, improving sensitivity.

Answer 1

The Correct Option is C

The sensitivity of a potentiometer is directly related to the potential gradient along its wire, which is defined as the voltage drop per unit length of the potentiometer wire. Mathematically, the potential gradient \( k \) is given by: \[ k = \frac{V}{L}, \] where \( V \) is the voltage across the wire and \( L \) is the length of the wire. When the current through the potentiometer wire is increased, the voltage drop across the wire increases proportionally, resulting in a higher potential gradient \( k \). A higher potential gradient means that even a small change in the length of the wire corresponds to a larger change in voltage, which improves the precision and accuracy of measurements. Therefore, increasing the current through the potentiometer wire increases the potential gradient and thereby increases the sensitivity of the potentiometer.