The electric potential on the surface of a charged spherical conductor of radius $5 \,cm$ is $200 \,V$. The work done in moving a charge of $+5 \,C$ from a point $A$ to another point $B$ situated at distances of $15 \,cm$ and $10 \,cm$ respectively from the centre of the sphere is (in $\,J$)

$A$ potential at a point $A$ is $-3 \ V$ and that at another point $B$ is $5 \ V$. What is the work done in carrying a charge of $5 \ mC$ from $B$ to $A$?

$A$ solid conducting sphere having a charge $Q$ is surrounded by an uncharged concentric conducting hollow spherical shell. Let the potential difference between the surface of the solid sphere and that of the outer surface of the hollow shell be $V$. If the shell is now given a charge $-3Q$,the new potential difference between the same two surfaces is:

If $3$ charges of magnitude $q$ each are placed at the vertices of an equilateral triangle of side $l \ cm$,what is the net potential energy of the system?

Two identical positive charges are placed at $x = -a$ and $x = a$. The correct variation of potential $V$ along the $x$-axis is given by:

Two conducting spheres of radii $r_1$ and $r_2$ are equally charged. The ratio of their potentials is (potential of $r_1$ to potential of $r_2$):