Macroscopic phenomenological properties of dielectrics

The electric field E inside dielectrics can be treated as a superposition of two fields the external field Eg and the depolarized field Ej, i.e., E = Eg -l- Ej, or in scalar form 

Namely this value has to be introduced into the Coulomb s law (4.1.1) in order to determine a force acting between two point charges in a medium with dielectric permeability s. 

the surface density of the bounded charges is numerically equal to the dielectric polarization. 

As experiments show, the isotropic dielectric polarization is proportional to the electric field strength E and coincides with it directionally (91 E). In the SI, (he relation between 91 and E is written as 

Dielectric susceptibility k characterizes the dielectric from the point of view of its ability to be polarized in the electric field. The dielectric susceptibility in the SI is numerically equal to dielectric polarization divided by Sq of the dielectric polarization in the field of the unit electrostatic field strength. 

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