Question: If the refractive index of a medium is 2.0, what is the maximum angle of incidence for total internal reflection when light travels to air?
Options:
Correct Answer: 60°
Solution:
Critical angle θc = sin⁻¹(n2/n1) = sin⁻¹(1.00/2.00) ≈ 30°; thus, maximum angle of incidence for total internal reflection is 60°.