An electric dipole is characterised by a vector quantity
where
q – The magnitude of the charge
2a – The separation between two charges
An electric dipole is created by the combination of equal and opposite charges by a separation of a certain distance.
Electric dipole moment is thus the product of the magnitude of either of the charges and the vector displacement from the negative to the positive charge.
Clearly, the electric dipole moment
Dimensional Formula of p
The direction of the dipole moment is always from the negative charge to the positive charge. The dimensional formula of an electric dipole is
The dimensional formula of magnetic or electric dipole moment is given by,
[M0 L1 T1 I1]Where,
- M = Mass
- I = Current
- L = Length
- T = Time
Units of p
(i) The SI unit of p is Coulomb metre (C m)
(ii) The practical unit of p is called debye (D)