An unpolarised light is incident at an interface of two dielectric media having refractive indices of 2 (incident medium) and 2 3 (refracted medium) respectively. To satisfy the condition that reflected and refracted rays are perpendicular to each other, the angle of incidence is
- 45
- 60
- 10
- 30
Answer
(2) 60
Solution
Reflected and refracted rays are perpendicular to each other when light is incident at the polarising (Brewster) angle iB.
By Brewster's law: iB = 2 1
iB = 2 32 = 3
iB = 60
Answer: (2)