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 ?
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