Question

light enters from air into water, which has refractive index of 1.33. Calculate the speed of light in water.

Answer 1

Speed of light in a medium = speed of light in air / refractive index 

V2 = 3 x 10^8 / 1.33 
=2.26 x 10^8 m/s (approx. )

Answer 2

Answer:

The speed of light in water is $2.26\times10^{8}$.

Explanation:

Given that,

Refractive index = 1.33

We know that,

The refractive index is given by

$n =\dfrac{c}{v}$....(I)

Where, n = refractive index

c = Speed of light in air

v = speed of light in medium

Put the value of n in equation (I)

$v = \dfrac{c}{n}$

$v = \dfrac{3\times10^{8}}{1.33}$

$v = 2.26\times10^{8}\ m/s$

Hence, The speed of light in water is $2.26\times10^{8}$.