Question

the refractive index of Glass and water with respect to the air are 3/2 and 4/3 respectively if the speed of light is plan is 2 × 10 raise to 8 metre per second find the speed of the light in water..

Answer 1

Actually, ng = 3/2 and nw = 4/3.

Absolute Refractive Index of a medium = Speed of light in vacuum/Speed of light in the medium

Speed of light in glass = 2 x 108 m/s
Speed of Light in Vacuum = (3/2) x 2 x 108 m/s = 3 x 108 m/s

Speed of light in water = (3 x 108 m/s)/(4/3)
                                        = 2.25 x 108 m/s