If the critical angle for total internal reflection from a medium to vacuum is 30°. Then the speed of light in the medium is?
Answer & explanation
Correct answer: option 4
Refractive index μ = 1/sinθc
= 1/sin30 =2
Refractive index μ = c/v
v = 3x108 / 2 = 1.5x108 m/s