Electric Susceptibility

Electric Susceptibility:

Whenever an external electric field is applied across a dielectric, a net dipole moment induced in it. The dipole moment induced depends upon the electric field applied on it.

Hence, the dipole moment induced per unit volume is given by

                 P ∝ E

Or             P = χe E   …………….(1)

Where χe is constant of proportionality and is known as electric Susceptibility.

From equation 1, we can write

             χe = P / E

If ,          E = 1

then.      χe = P.

Hence, the electric susceptibility is defined as the dipole moment induced per unit volume in a dielectric material when an unit electric field is applied across it.