Find the potential at points $A$ and $D$ if potential at point $B$ is equal to zero.

Find the equivalent resistance between the terminals $X$ and $Y$.

The total current supplied to the circuit by the battery is

In the figure shown, the current flowing through $2R$ is

In the circuit shown, the current through the $4 \mathrm{\Omega }$ resistor is $1 \mathrm{A}$ when the points $P$ and $M$ are connected to a $\mathrm{DC}$ voltage source. The potential difference between the points $M$ and $N$ is

Find the current flowing through the resistance $R_1$ of the circuit shown in figure if the resistances are equal to $R_1=10 \mathrm{\Omega }, R_2=20 \mathrm{\Omega }$, and $R_3=30 \mathrm{\Omega }$, and the potentials of points $1, 2$ and $3$ are equal to ${\mathrm{\phi }}_1 = 10 \mathrm{V}, {\mathrm{\phi }}_2 = 6 \mathrm{V},$ and ${\mathrm{\phi }}_3 = 5 \mathrm{V}$.

 Consider the following two statements: 

(A) Kirchhoff s junction law follows from conservation of charge.
(B) Kirchhoff's loop law follows from the conservative nature of the electric field.

In the given current distribution, what is the value of $I$?

The figure below shows currents in a part of electric circuit. The current $I$ is