The speed of light in glass

The speed of light in Ruby is

The refractive index of air with respect to glass is 0.666
Step-by-step explanation:
The refractive index is the degree of diffraction of a light beam passing from one medium to another. It can also be defined as the ratio of the speed of light in an empty space to the speed of light in a material. The equation is given as

Given data:


Velocity of light in vacuum, c =

We need to find velocity of glass, ruby and refractive index ratio of air and glass
To find velocity of glass,


To find velocity of ruby,


To calculate the refractive index of air with respect to glass: =

We know, the value of the refractive index of air is 1
The value of the refractive index of glass is 1.5
So, the ratio of them should be
