A parallel beam of light is incident from air at an angle α on the side PQ of a right angled triangular prism of refractive index n = 2 . Light undergoes total internal reflection in the prism at the face PR when α has a minimum value of 45 o . The angle θ of the prism is:

Question

A parallel beam of light is incident from air at an angle α on the side PQ of a right angled triangular prism of refractive index n = 2 . Light undergoes total internal reflection in the prism at the face PR when α has a minimum value of 45 o . The angle θ of the prism is:, 15 o, 22.5 o, 30 o, 45 o

MARKS App · Accepted Answer

1 sin ⁡ 45 o = 2 sin ⁡ r 1 r 2 - r 1 = θ θ = 45 o - 30 o ⇒ θ = 15 o

Search any question & find its solution

Looking for more such questions to practice?