Question

the refractive index of glass is 0.90 and tye speed of light in air is 3×10^8 ms^-1 . calculate the speed of light in glass​

Answer 1

First let us write all the given quantities...

Speed of light in air                 = 3 X 10^8 ms^-1

Refractive Index of the glass  = 0.90

Now let us find the speed of light in the taken glass....

We know that,

Refractive Index of an object = Speed of light in the object

                                                         Speed of light in air

=>                                     0.90 = Speed of light in glass X 1 / 3 X 10^8 ms^-1

=>      (3 X 10^8 ms^-1) X 0.90 = Speed of light in glass

=>                  2.7 X 10^8 ms-1 = Speed of light in glass