Question

calculate speed of light in water of refractive index 4/3. given speed of light in air = 3*10^8m/s

Answer 1

The refractive index of water = Speed of light in air / Speed of light in water

Given :

Refractive Index = 4 / 3

Speed of light in air = 3 * 10⁸ m/s

We have to find Speed of light in water.

Substituting the values in the formula for refractive index :

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

4 / 3 = 3 * 10⁸ / Speed of light in water

Speed of light in water =  3 * 10⁸ * 3 / 4

Speed of light in water = 2.25 * 10⁸

Thus,

Speed of light in water is 2.25 * 10⁸ m/s

Answer 2

R.I of water Speed of light in vacuum / speed = of light in water

4/ 3 = 3 × 10^8 / speed of light in water

speed of light in water = 3 × 10^8 / 3/ 4

= 2.25 x 10 m/s