Question

In the network shown cell E has internal resistance r and the galvanometer shows zero deflection. If the cell is replaced by a new cell of emf 2E and internal resistance 3r keeping everything else identical, then ______.

Options

• The galvanometer will show deflection of 10 divisions.

• The galvanometer show zero deflection

• Current will flow from B to A.

• Current will flow from A to B.

Answer 1

In the network shown cell E has internal resistance r and the galvanometer shows zero deflection. If the cell is replaced by a new cell of emf 2E and internal resistance 3r keeping everything else identical, then the galvanometer show zero deflection.

Explanation:

In the given circuit diagram, galvanometer shows zero deflection, hence it is a Wheatstone balanced circuit.

Hence, V_A = V_B

On replacing a new cell of emf 2E and internal resistance 3r, no effect occurs on balanced condition of bridge, i.e. V_A = V_B.

Hence, the galvanometer will shows zero deflection.