Question

Q6) State the laws of refraction of light. If the speed of light in vacuum is 3 X 109 m/s, find the speed of light in a medium of absolute refractive index 1.5.​

Answer 1

Answer:

Laws of refraction of light:-

1) All the three rays (i.e. refracted ray , incident ray and normal ray ) lies in the same plane .

2) sin of angle of incidence by sin of angle of refraction is equal to a constant .

Explanation:

Absolute refractive index= speed of light in vaccum/ speed of light in a medium .

Given:- speed of light in vaccum =

3× 10^8 m/s

refractive index = 1.5

Let speed of light in medium =k

Substitute the values in the relation ,

1.5= 3 × 10^8/k

k= 3×10^8/1.5

k=2×10^8

So speed of light in medium is

2×10^8 m/s.