Electrical Engineering ⇒ Topic : Refraction of Electric Flux

Refraction of Electric Flux

Refraction of Electric Flux

When electric flux passes from one uniform dielectric medium to another of different permittivities, the electric flux gets refracted at the boundary of the two dielectric media. Under this condition, the following two conditions exist at the boundary (called boundary conditions) :

                                                         figure (a)

(1) The normal components of electric flux density are equal i.e.

                                               D_1N = D_2N

(2)The tangential components of electric field intensities are equal i.e.

                                                   E_1t = E_2t

Fig. (a) shows the refraction of electric flux at the boundary BB of two dielectric media of permittivities ε₁ and ε₂ . As shown, the electric flux in the first medium (ε₁) approaches the boundary BB at an angle θ₁ and leaves it at  θ₂ . D_1N = D_2N the normal components of D₁ and D₂ while  E_1t = E_2t are the tangential components of E₁ and E₂. Refering to Fig.(a).