In the circuit shown,$E_1 = 4.0 \ V, R_1 = 2 \ \Omega, E_2 = 6.0 \ V, R_2 = 4 \ \Omega$ and $R_3 = 2 \ \Omega$. The current $I_1$ is : ................ $A$

The potential difference $(V_A - V_B)$ between the points $A$ and $B$ in the given figure is (in $V$)

Three identical batteries each of $emf\ 4\ V$ and negligible internal resistance are connected as shown in the figure. The potential difference between points $A$ and $G$ $(V_A - V_G)$ is ................ $V$.

What is the current in $A$ flowing through $BD$ in the given circuit?

$A$ Wheatstone's bridge is balanced with a resistance of $625\, \Omega$ in the third arm,where $P, Q$ and $S$ are in the $1^{st}, 2^{nd}$ and $4^{th}$ arm respectively. If $P$ and $Q$ are interchanged,the resistance in the third arm has to be increased by $51\,\Omega$ to secure balance. The unknown resistance in the fourth arm is ............. $\Omega$.

$ABCD$ is a square where each side is a uniform wire of resistance $1\,\Omega$. $A$ point $E$ lies on $CD$ such that if a uniform wire of resistance $1\,\Omega$ is connected across $AE$ and a constant potential difference is applied across $A$ and $C$,then $B$ and $E$ are equipotential.