Question

please answer the following question​

Answer 1

Answer:

Refractive index of a medium is defined as the ratio of speed of light in vacuum to speed of light in the medium.

given  :vg = 2×10^8 m/s

Let velocity in vacuum = v

refractive index of glass is 3/2. 

ng =v/vg

3/2 =v/2×10^8

V=(3×2×10^8) /2

=3×10^8 m/s

So speed of light in vacuum is : 3×10^8 m/s

Now,

nw =v/vw

4/3=(3×10^8) /vw

vw= (3×3×10^8) /4

=2.25×10^8 m/s

So speed of light in water is :

2.25×10^8 m/s