To achieve higher sensitivity in a potentiometer, which of the following is essential?

A larger length of the potentiometer wire
A higher emf of the auxiliary (driver) battery
A higher specific resistance of the wire
None of the above

Correct answer: A larger length of the potentiometer wire

Solution

A smaller potential gradient lets a given emf balance over a longer length, giving finer resolution; increasing wire length (for a fixed drop) reduces the gradient and raises sensitivity.

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