Positive and negative point charges of equal magnitude are kept at $(0, 0, a/2)$ and $(0, 0, -a/2)$,respectively. The work done by the electric field when another positive point charge is moved from $(-a, 0, 0)$ to $(0, a, 0)$ is

Prove that a closed equipotential surface with no charge within itself must enclose an equipotential volume.

In moving from $A$ to $B$ along an electric field line,the electric field does $6.4 \times 10^{-19} \, J$ of work on an electron. If $\phi_1$ and $\phi_2$ are equipotential surfaces,then the potential difference $(V_C - V_A)$ is.....$V$.

The figure shows three points $A$,$B$,and $C$ in a region of uniform electric field $\overrightarrow{E}$. The line $AB$ is perpendicular and $BC$ is parallel to the field lines. Which of the following relations holds good? Let $V_A$,$V_B$,and $V_C$ represent the electric potential at points $A$,$B$,and $C$ respectively.

Write the characteristics of equipotential surface.

Equipotential surfaces at a very large distance from a collection of charges whose total sum is not zero are approximately . . . . . . .