Question

Define an electric dipole. Derive an expression for the electric field
intensity at a point situated at a distance r along the axial line of an electric
dipole. What is the electric field when r>> length of dipole.​

Answer 1

An electric dipole is defined as a couple of opposite charges q and –q separated by a distance d.

The direction of electric dipoles in space is always from negative charge -q to positive charge q. The midpoint q and –q is called the centre of the dipole. The simplest example of an electric dipole is a pair of electric charges of two opposite signs and equal magnitude separated by distance.