The electric field due to a dipole at a distance $r$ on its axis is

The ratio of electric fields on the axis and at the equator of an electric dipole is

An electric dipole is placed along the $x$-axis with its center at the origin. The line $OP$ makes an angle of $\frac{\pi}{3}$ with the $x$-axis. If the electric field at point $P$ makes an angle $\theta$ with the $x$-axis,then $\theta$ is equal to:

The electric field at a point on the equatorial line of a dipole and the direction of the dipole moment:

$A$ point $Q$ lies on the perpendicular bisector of an electric dipole with dipole moment $p$. If the distance of $Q$ from the dipole is $r$ (where $r$ is much larger than the size of the dipole),then the electric field at $Q$ is proportional to:

Two parallel disks each having radius $R$ are separated by a distance $l$. The surface charge densities are $\sigma$ and $-\sigma$. The electric field at point $P$,a large distance $r$ along the axis of the disks is: