Question

Light rays in a material with index of refrection 1.33 can undergo total internal reflection when they strike the interface with another material at a critical angle of incidence. Find the second material's index of refraction when the required critical angle is 71.50 index of refraction:

Answer 1

Here,

let the refractive index of second material is n

Using Snell's law for total internal reflection

1.33 * sin(71.5) = n * sin(90 degree)

n = 1.26

the material's refractive index is 1.26