In the following electrical network,the value of $I$ is (in $A$)

Find the potential difference $(V_A - V_B)$ for the given circuit.

Figure $(i)$ below shows a Wheatstone's bridge in which $P, Q, R$ and $S$ are fixed resistances,$G$ is a galvanometer and $B$ is a battery. For this particular case,the galvanometer shows zero deflection. Now,only the positions of $B$ and $G$ are interchanged,as shown in figure $(ii)$. The new deflection of the galvanometer

In the circuit shown,the currents (in $A$) through the $50\; V$ and $30\; V$ batteries are,respectively:

In the following diagram,the Wheatstone bridge is balanced when we interchange the resistances of:

In the given circuit diagram,find the current passing through the wire $CD$ (in ampere).