## Quick Reference

_{m}. The dimensionless quantity describing the contribution made by a substance when subjected to a magnetic field to the total magnetic flux density present. It is equal to μ_{r} − 1, where μ_{r} is the relative permeability of the material. Diamagnetic materials have a low negative susceptibility, paramagnetic materials have a low positive susceptibility, and ferromagnetic materials have a high positive value.

_{e}. The dimensionless quantity referring to a dielectric equal to *P*/ε_{0}*E*, where *P* is the electric polarization, *E* is the electric intensity producing it, and ε_{0} is the electric constant. The electric susceptibility is also equal to ε_{r} − 1, where ε_{r} is the relative permittivity of the dielectric.

**From:**
susceptibility
in
A Dictionary of Physics »

*Subjects:*
Physics.