Question

Draw the circuit diagram of a Wheatstone bridge. Obtain the condition when no current flows through the galvanometer in it.

Derive the relation between the current and the drift velocity of free electrons in a conductor. Briefly explain the variation of resistance of a conductor with rise in temperature.

An ammeter, together with an unknown resistance in series is connected across two identical batteries, each of emf 1·5 V, connected (i) in series, and (ii) in parallel. If the current recorded in the two cases be (1/2) A and (1/3) A respectively, calculate the internal resistance of each battery.

State Kirchhoff's rules. Use them to obtain the condition of balance for a Wheatstone Bridge.