Question

11. While performing an experiment with potentiometer (Fig.)
it was found that the deflection is one sided and
() the deflection decreased while moving from one end A of
the wire to the end B; (ii) the deflection increased, while A
the jockey was moved towards the end B.
(a) Which terminal + or -ve of the cell E, is connected
at X in case (1) and how is E related to E?
(b) Which terminal of the cell E, is connected at X in case (11)?
[NCERT Exemplar]​

Answer 1

Answer:

Explanation:

If the value of R is increased, the current through the wire will decrease which in turn decreases the potential difference across AB, and hence potential gradient (k) across AB decreases.

Since, at neutral point, for given emf of cell, l increases as potential gradient (k) across AB has decreased because E’ = kl

Thus, with the increase of l, which will result in increase in balance length. So, jockey J will shift towards B.