Question

If the critical angle of total internal reflection from a medium to vaccum is 30° then velocity of light in the medium is

Answer 1

Answer:

Critical angle for total internal reflection

θc=30°

As we know, refractive index of air medium

nair =1

Refractive index of the medium n= 1/ sinθc

n = 1/ sin 30°

= 1/ 0.5

n = 2

Velocity of light in medium v= c/n

v = 3× 10^8 /2

= 1.5× 10^8 m/s