Question

The speed of light in water is 2.25 × 10⁸ m/s. If the speed of light in vacuum be 3 × 10⁸ m/s, calculate the refractive index of water.

Answer 1

Given:
Speed of light in water = 2.25 × 10⁸ m/s
Speed of light in vacuum = 3 × 10⁸ m/s
Refractive index of water = ?
Applying the formula for refractive index, we get:​
Refractive index of a medium = (Speed of light in vacuum) / (Speed of light in the medium)
For water:
Refractive index of water = (Speed of light in vacuum) / (Speed of light in water)
= (3 × 10⁸) / (2.25 × 10⁸)
= 1.33
Thus, the refractive index of water is 1.33.