The unit of the physical quantity obtained by the line integral of the electric field is . . . . . . .

Two particles $A$ and $B$ having the same mass have charges $+q$ and $+4q$ respectively. When they are allowed to fall from rest through the same electric potential difference,the ratio of their speeds $v_A$ to $v_B$ will be:

$A$ pellet carrying a charge of $0.5 \, C$ is accelerated through a potential difference of $2000 \, V$. The kinetic energy attained by the pellet is:

What is the electric potential at the center $O$ of a circle of radius $0.4 \ m$ with the charges arranged as shown in the figure?

As shown in the figure,charges $+q$ and $-q$ are placed at the vertices $B$ and $C$ of an isosceles triangle. The potential at the vertex $A$ is

Two point charges $q_1$ and $q_2$ are separated by a distance $d$. What is the increase in potential energy of the system when $q_2$ is moved towards $q_1$ by a distance $x$? $(x < d)$ (where $\frac{1}{4 \pi \varepsilon_0} = K$ is a constant).