Unpolarised light is incident from air on a plane surface of a material of refractive index $\mu$. At a particular angle of incidence 'i', it is found that the reflected and refracted rays are perpendicular to each other. Which of the following options is correct for this situation?

Question

( A ) Reflected light is polarised with its electric vector parallel to the plane of incidence
( B ) Reflected light is polarised with its electric vector perpendicular to the plane of incidence
( C ) $i = \sin^{-1} (\frac{1}{\mu})$
( D ) $i = \tan^{-1} (\frac{1}{\mu})$