The points having equal potentials are:

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

Find the equation of the equipotential surface for an infinite cylinder of radius $r_0$,carrying a charge of linear density $\lambda$.

As per the diagram,a point charge $+q$ is placed at the origin $O$. The work done in taking another point charge $-Q$ from point $A$ [coordinates $(0, a)$] to point $B$ [coordinates $(a, 0)$] along the straight path $AB$ is:

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

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: