Consider a light ray travelling in air is incident into a medium of refractive index 2 n . The incident angle is twice that of refracting angle. Then, the angle of incidence will be

Step-by-step solution

Let angle of incidence be θ , then angle of refraction θ 2 . From Snell's law, we can write, 1 × sin θ = 2 n × sin θ 2 , 2 sin θ 2 cos θ 2 = 2 n sin θ 2 cos θ 2 = n 2   ⇒ θ = 2 cos - 1 n 2