Question

total internal reflection between two materials is seen to occur if a critical angle of 60 degrees is exceeded. if the index of refraction of the material that the light is entering is 1.98,find the inndex of refraction of the material in which the light is originating.

Answer 1

Snells Law says that, for the limiting critical reflection angle,
1.98 sin 60 = N2*sin 90 = N2
N2 = 1.715