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

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.

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$: Work done by an electric field on moving a positive charge on an equipotential surface is always zero.
Reason $(R)$: Electric lines of force are always perpendicular to equipotential surfaces.
In the light of the above statements,choose the most appropriate answer from the options given below:

$A$ uniform electric field of magnitude $E = 100 \ V/m$ is directed along the line $y = x + 3$. Find the potential difference $V_A - V_B$ between points $A(3, 1)$ and $B(1, 3)$.

$A$ charge $Q$ is placed at the centre of a circle of radius $10 \ cm$. Find the work done in moving a charge $q$ between any two points lying on the arc of the circle.