The electric potential at a point on the axis of an electric dipole is proportional to $[r=$ distance between the centre of the electric dipole and the point].

Two charges $+q$ and $-q$ are kept at a certain distance apart. Then, at any point on the perpendicular bisector of the line joining the two charges:

The angle between the electric field and the dipole moment at any point on the equatorial plane of an electric dipole is . . . . . . . (in $^{\circ}$)

Two charged particles each of mass $9.8 \text{ g}$ and charges $+20 \mu\text{C}$ and $-20 \mu\text{C}$ are attached to the two ends of a massless and rigid uniform non-conducting rod of length $50 \text{ cm}$. This arrangement is held in a uniform electric field of $12.1 \text{ N/C}$,such that the rod makes a very small angle with the field direction. If the rod is set free,the minimum time needed for the rod to become parallel to the direction of the electric field is ................ seconds.

Three identical dipoles are arranged as shown below. What will be the net electric field at $P$ $\left( {k = \frac{1}{{4\pi {\varepsilon _0}}}} \right)$?

On the axis and on the equator of an electric dipole for all points . . . . . . .