Question

In the figure a long uniform potentiometer wire AB is having a constant potential gradient along its length. The null points for the two primary cells of emf ɛ₁, and ɛ₂, connected in the manner shown are obtained at a distance of 120 cm and 300 cm from the end A. Find (i) ɛ₁/ɛ₂ and

(ii) position of null point for the cell ɛ₁.

How is the sensitivity of a potentiometer increased ?

Answer 1

(Award full marks for any other correct method)

By decreasing potential gradient, the. sensitivity of a potentiometer is increased.

[Or through increasing length, reducing potential drop across wire, increasing resistance input in series with the main cell etc.]