A ray of light which is traveling in a medium of refractive index n1​=1.860 becomes incident on a less dense medium of refractive index n2​=1.440. The free space wavelength (λ) of the light ray is 1100 nm.
a) What should be the minimum incidence angle for TIR?
b) What is the phase change in the reflected wave when θi=67∘ and when θi=90∘ ? c)What is the penetration depth of the evanescent wave into medium 2 when θi=70∘ and when θi=90∘ ?