While doing an experiment with potentiometer (Fig 3.5) it was found that the deflection is one sided and (i) the deflection decreased while moving from one end A of the wire to the end B; (ii) the deflection increased. While the jockey was moved towards the end B.

(i) Which terminal +or –ve of the cell E₁, is connected at X in case (i) and how is E₁ related to E?

(ii) Which terminal of the cell E₁ is connected at X in case (ii)?

Question

While doing an experiment with potentiometer (Fig 3.5) it was found that the deflection is one sided and (i) the deflection decreased while moving from one end A of the wire to the end B; (ii) the deflection increased. While the jockey was moved towards the end B.

(i) Which terminal +or –ve of the cell E₁, is connected at X in case (i) and how is E₁ related to E?

(ii) Which terminal of the cell E₁ is connected at X in case (ii)?

Philoid · Accepted Answer

(i) In case (i), the deflection decreases, magnitude of current in the wire decreases and potential difference across A and jockey decreases. The deflection is one sided. This is only possible if positive terminal of E₁ is connected at X and E₁>E.

(ii) In case (i), the deflection increases, magnitude of current in the wire increases and potential difference across A and jockey increases. This implies, negative terminal of E₁ is connected at X.