(a) A ray of light falls normally on a face of a glass slab. What are the values of angle of incidence and angle of refraction of this ray?
(b) Light enters from air to a medium ‘X’. Its speed in medium ‘X’ becomes 1.5 x ${{10}^{8}}$ m ${{s}^{-1}}$. Speed of light in air is 3 x ${{10}^{8}}$ m${{s}^{-1}}$ . Find the refractive index of medium ‘X’.
(a) Both the angles are zero.
(b) Given v = 1.5 x ${{10}^{8}}$ m ${{s}^{-1}}$, c = 3.0 x ${{10}^{8}}$ m ${{s}^{-1}}$
Using, n= c/v
we have n= 3.0 x ${{10}^{8}}$ m ${{s}^{-1}}$ / 1.5 x ${{10}^{8}}$ m ${{s}^{-1}}$ = 2