Question

What is the critical angle of a light beam passed from a medium (n=2) to a medium (n=1.2)?

Answer 1

θ_c = 36.87°

Step-by-step explanation:

Index of refraction for index medium; n_i = 2

Index of refraction for Refractive medium; n_r = 1.2

Formula to find the critical angle is given;

n_i(sin θ_c) = n_r(sin 90)

Where θ_c is critical angle.

Thus;

2 × (sin θ_c) = 1.2 × 1

(sin θ_c) = 1.2/2

(sin θ_c) = 0.6

θ_c = sin^(-1) 0.6

θ_c = 36.87°