question_answer

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?                                                                                         [NEET - 2018]

A)  \[i={{\sin }^{-1}}\left( \frac{1}{\mu } \right)\]

B)  Reflected light is polarised with its electric vector perpendicular to the plane of incidence

C)  Reflected light is polarised with its electric vector parallel to the plane of incidence

D)  \[i={{\tan }^{-1}}\left( \frac{1}{\mu } \right)\]

Correct Answer: B

Solution :

[b] When reflected light rays and refracted rays are perpendicular, reflected light is polarised with electric field vector perpendicular to the plane of incidence.

Also, \[\tan \text{ i=}\mu \](Brewster angle)