Question

Light enters from air to water which has a refractive index of 1.33. Calculate the speed of light in water.

Answer 1

n = c/v=1.33
here
c=3*10^8m/s
so
v = c/n 
or
n = 3*10^8/1.33
so speed of light in water 
v=2.26*10^8m/s

Answer 2

Answer:

2.25 × 10⁸ m / sec

Explanation:

Given :

Refractive index of water = 1.33

Speed of light in air = 3 × 10⁸ m / sec.

We know :

Refractive index = Speed of light in air / Speed of light in water

Speed of light in water = Speed of light in air / Refractive index.

Putting value we get :

Speed of light in water = 3 × 10⁸ m / sec / 1.33 .

Speed of light in water = 2.25 × 10⁸ m / sec

Hence speed of light in water is 2.25 × 10⁸ m / sec