Question

The refractive index of glass is 1.5. Calculate the speed of light in glass. The speed of light in air is 3.0 × 10⁸ ms⁻¹.

Answer 1

Given:
Refractive index of glass = 1.5
Speed of light in air = 3.0 × 10⁸ m/s
Speed of light in glass = ?
Applying the formula for refractive index, we get:
Refractive index of a medium = (Speed of light in air)/(Speed of light in medium)
For glass:
Refractive index of glass = (Speed of light in air)/(Speed of light in glass)
(Speed of light in glass) = (Speed of light in air)/(Refractive index of glass)
= (3.0 × 10⁸)/1.5
= 2.0 × 10⁸ m/s