Question

Speed of light in air is 3 x 10⁸ ms^-1 and the refractive index of a medium is 1.5.Find the speed of light in medium.

Answer 1

Speed of light  in air c = 3 x 10⁸ ms^-1

Refractive index of a medium μ = 1.5

To find : Speed of light in medium v = ?

Formula :

μ =\(\frac{c}{v}\)

1.5 = \(\frac{3 \times 10^8}{v}\)

v = \(\frac{3 \times 10^8}{1.5}\)

v = 2 x 10⁸ ms^-1

Speed of light in medium v = 2 x 10⁸ ms^-1