A uniform plane wave having parallel polarization is obliquely incident on an air-dielectric interface as shown in figure. If the wave has an electric field E = 10 V/m. Find
(i) the angle of incidence 9, for which there is no reflection of the wave, and
(ii) the surface charge density at the interface.
\theta BBrewster angle,
\begin{aligned}\tan \left(\theta_{b}\right) &=\sqrt{\frac{E_{r_{2}}}{E_{r_{1}}}}=2 \\\theta b &=6.3 .4^{\circ}\end{aligned}(ii) E _{t}= E _{i}
\begin{gathered}\frac{D_{t}}{E_{2}}=\frac{D_{i}}{E_{1}} \Rightarrow D_{t}=\frac{E_{2}}{E_{1}} D_{i}=\frac{E_{0} E_{r}}{E_{0}}=4 D_{i} \\P_{s}=P_{t}-D_{i}=3 D_{i}=3 E_{0} E_{i}=0.26 nc / m ^{2}\end{gathered}