ELECTRIC DIPOLE
An arrangement of equal and opposite point charges q and -q, separated by a distance 2l. The line connecting the two charges defines a direction in space.. The mid-point of locations of -q and q is called the center of the dipole.
If q and -q be two charges separated by distance `2l`. The dipole moment of the dipole is:
`vecP = q (2vecl)`
a)It is a vector quantity and is directed from `- ve` charge towards the ` +ve` charge. The line joining `-q` to `+q` is known as the axis of the dipole.
b)The total charge of the electric dipole is obviously zero. This does not mean that the field of the electric dipole is zero. Since the charge q and -q are separated by some distance, the electric fields due to them, when added, do not exactly cancel out. However, at distances much larger than the separation of the two charges forming a dipole (r >> 2l), the fields due to q and -q nearly cancel out.
If q and -q be two charges separated by distance `2l`. The dipole moment of the dipole is:
`vecP = q (2vecl)`
a)It is a vector quantity and is directed from `- ve` charge towards the ` +ve` charge. The line joining `-q` to `+q` is known as the axis of the dipole.
b)The total charge of the electric dipole is obviously zero. This does not mean that the field of the electric dipole is zero. Since the charge q and -q are separated by some distance, the electric fields due to them, when added, do not exactly cancel out. However, at distances much larger than the separation of the two charges forming a dipole (r >> 2l), the fields due to q and -q nearly cancel out.