The refractive index of air with respect to glass is expressed as gμa = sin isin r.
(a) Write down a similar expression for gμa in terms of the angles i and r.
(b) If angle r = 90∘, what is the corresponding angle i called?
(c) What is the physical significance of the angle i in part (b)?
(b) If refractive angle, r = 90∘, the corresponding angle of incidence, 'i' will be equal to the critical angle.
(c) If the angle of incidence exceeds the value of 'i' obtained in part (b) (i.e., critical angle), the total internal reflection will occur.