#) Electric Dipole: An electric dipole is a pair of equal and opposite point charges q and –q, separated by a distance 2a. The line connecting the two charges defines a direction in space.
*) By convention, the direction from –q to q is said to be the direction of the dipole. The mid-point of locations of –q and q is called the centre of the dipole.
*) The total charge of the electric dipole is obviously zero. This does not mean that the field of the electric dipole is zero.
*) The electric field due to a dipole falls off, at large distance, faster than like 1/r 2 (the dependence on r of the field due to a single charge q).
*) The electric field produced by a dipole is known as dipole field.