If the electric potential at a point on the surface of a hollow conducting sphere of radius $R$ is $V$,then the electric potential at a point which is at distance $\frac{R}{3}$ from the centre of the sphere is

$A$ hollow metal sphere of radius $5\, cm$ is charged so that the potential on its surface is $10\, V$. The potential at the centre of the sphere is.....$V$

$A$ charge $2\,\mu C$ is taken from infinity to a point in an electric field,without changing its velocity. If the work done against the electric forces is $20\,\mu J$,then the potential at that point will be.....$V$

$A$ charge $Q$ is uniformly distributed over a rod $AB$ of length $L$ as shown in the figure. The electric potential at point $O$,which is at a distance $L$ from end $A$,is:

Twenty-seven drops of water of the same size are equally and similarly charged. They are then united to form a bigger drop. By what factor will the electrical potential change?

Two charges $+q$ and $-q$ are placed at points $A$ and $B$ respectively, which are at a distance $2L$ apart. $C$ is the midpoint of $A$ and $B$. The work done in moving a charge $+Q$ along the semicircle $CSD$ $(W_1)$ and along the line $CBD$ $(W_2)$ are: