In a potentiometer, the sensitivity can be increased by: MCQ with Answer and Explanation

In a potentiometer, the sensitivity can be increased by:
A. Increasing the current in the primary circuit
B. Decreasing the length of the wire
C. Using a thicker wire
D. Increasing the length of the wire
Answer: Option D
Solution (By JKSSB Mock Tests)
Potentiometer sensitivity (ability to detect small EMF changes) increases with longer wire because potential gradient (V/cm) decreases, allowing finer measurement of balancing length. Sensitivity ∝ length of wire. Decreasing length (B) reduces sensitivity; increasing current (C) increases potential gradient, reducing sensitivity; thicker wire (D) reduces resistance but doesn't directly affect sensitivity if current adjusted. Memory tip: 'Longer potentiometer wire ⇒ smaller potential gradient ⇒ higher sensitivity'. This experimental physics concept is frequently tested in competitive exams. Always link sensitivity to potential gradient: smaller gradient allows detection of smaller voltage differences.

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