Question

What is meant by electric susceptibility?

Answer 1

Electric susceptibility (often represented as \( \chi_e \)) is a measure of how easily a material becomes polarized when exposed to an electric field. It tells us how much the material's electric dipoles (positive and negative charges) align with the applied electric field.

In simpler terms, electric susceptibility indicates how much a material will "react" to an electric field and create its own internal electric field in the opposite direction. The stronger the electric susceptibility, the more the material will become polarized (its charges will shift in response to the electric field).

Electric susceptibility is related to the material's permittivity \( \varepsilon \) through the formula:

\[
\varepsilon = \varepsilon_0 (1 + \chi_e)
\]

where:

1. \( \varepsilon_0 \) is the permittivity of free space (a constant),
   

1. \( \varepsilon \) is the permittivity of the material (how easily it can be polarized),
   

1. \( \chi_e \) is the electric susceptibility.
   

If \( \chi_e \) is large, the material is highly polarizable, which means it's a good dielectric material. If \( \chi_e \) is small, the material is weakly polarizable.

In summary, electric susceptibility tells us how much a material will respond to an electric field by becoming polarized.