$A$ uniform electric field of magnitude $100 \ V/m$ in space is directed along the line $y = 3 + x$. Find the potential difference between point $A(3, 1)$ and $B(1, 3)$ in Volts.

In an electric field due to charge $Q$,a charge $q$ moves from point $A$ to $B$ along an arc of a circle centered at $Q$,as shown in the figure. The work done is ($\varepsilon_0=$ permittivity of free space).

Draw an equipotential surface for a uniform electric field.

Which of the following figures shows the correct equipotential surfaces of a system of two positive charges?

The figure shows three points $A, B$ and $C$ in a uniform electric field $(\overrightarrow{E})$. The line $AB$ is perpendicular to $BC$ and $BC$ is parallel to $\overrightarrow{E}$. If $V_A, V_B$ and $V_C$ are the potentials at $A, B$ and $C$ respectively,then the correct option is

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