Consider a cube of uniform charge density $\rho$. The ratio of electrostatic potential at the centre of the cube to that at one of the corners of the cube is

A charge $Q$ is distributed over two concentric conducting thin spherical shells radii $r$ and $R$ $( R > r ) .$ If the surface charge densities on the two shells are equal, the electric potential at the common centre is

The electric field $\vec E$  between two points is constant in both magnitude and direction. Consider a path of length d at an angle $\theta  = 60^o$  with respect to field lines shown in figure. The potential difference between points  $1$ and $2$  is

An electric dipole is situated in an electric field of uniform intensity $E$ whose dipole moment is $p$ and moment of inertia is $I$. If the dipole is displaced slightly from the equilibrium position, then the angular frequency of its oscillations is

An electric dipole of dipole moment $\vec P$ is lying along a uniform electric field $\vec E$ . The work done in rotating the dipole by $90^o$ is

A hollow metal sphere of radius $5\,cm$ is charged such that the potential on its surface is $10\,V$. The potential at a distance of $2\,cm$ from the centre of the sphere.......$V$