When the angle of incidence is 60° on the surface of a glass slab, it is found that the reflected ray is completely polarised. The velocity of light in glass is

Options

(a) √2 x 10⁸ m/s
(b) √3 x 10⁸ m/s
(c) 2 x 10⁸ m/s
(d) 3 x 10⁸ m/s

Correct Answer:

√3 x 10⁸ m/s

Explanation:

From Brewster’s law μ = tan iᴘ

c/v = tan 60° = √3

v=c / √3 = 3 × 10⁸ / √3

= √3 × 10⁸ m/sec