Question

The angle of incidence at which reflected light is totally polarized for reflection from air to glass (refractive index n), is

• A. $ {{\sin }^{-1}}(n) $
• B. $ {{\sin }^{-1}}(1/n) $
• C. $ {{\tan }^{-1}}(1/n) $
• D. $ {{\tan }^{-1}}(n) $

Answer 1

Answer: (D)

The particular angle of incidence for which reflected light is totally polarized for reflection from air to glass, is called the angle of polarisation $ ({{i}_{p}}) $ (Brewsters law). Accordingly, $ n=\text{ }tan\text{ }{{i}_{p}} $ $ \Rightarrow $ $ {{i}_{p}}={{\tan }^{-1}}(n) $ where $ n= $ refractive index of glass.