Question 2.40: Calculate the change of electric field as it crosses an inte...

Since there is no surface charge between the two surfaces, we know that the normal components of the displacement flux density are continuous

ε₁ E₁ cos θ₁ = ε₂ E₂ cos θ₂

The continuity of the tangential components of the electric field is given by

E₁ sin θ₁ =  E₂ sin θ₂

The ratio of these two terms gives.

\frac{\tan \theta_{1}}{\tan \theta_{2}}=\frac{\varepsilon_{1}}{\varepsilon_{2}}

This example indicates that the electric field can be bent with different dielectrics.