The angle between an equipotential surface and the electric lines of force is .......$^o$.

The figure shows three points $A, B$ and $C$ in a region of uniform electric field $E$. The line $A B$ is perpendicular and $B C$ is parallel to the field lines. Then,which of the following holds good? ($V_{A}, V_{B}$ and $V_{C}$ represent the electric potential at points $A, B$ and $C$,respectively)

How much work is required to move a charge $(-q)$ from point $A$ to point $C$ in the presence of a charge $+Q$ at point $B$ as shown in the figure?

There are two equipotential surfaces as shown in the figure. The distance between them is $r$. If a charge of $-q \text{ C}$ is moved from surface $A$ to surface $B$,the resultant work done will be:

An electric charge $10^{-3} \mu C$ is placed at the origin $(0, 0)$ of an $X-Y$ coordinate system. Two points $A$ and $B$ are situated at $(\sqrt{2}, \sqrt{2})$ and $(2, 0)$ respectively. The potential difference between the points $A$ and $B$ will be.......$V$.

$A$ hollow conducting sphere is placed in an electric field produced by a point charge placed at $P$ as shown in the figure. Let $V_A, V_B, V_C$ be the potentials at points $A, B,$ and $C$ respectively. Then: