If c is the velocity of light in free space, the time taken by light to travel a distance x in a medium refractive index μ is

Options

(a) x/c
(b) μx/c
(c) x/μc
(d) c/μx

Correct Answer:

μx/c

Explanation:

Velocity of light in a medium v = c / μ
We known time taken t = x / v
⇒ t = x / (c/μ) = μx / c