Question

The refractive index of a material is 1.33. If the velocity of light in vacuum is 3 × 10⁸ ms⁻¹, find the velocity of light in the material.

Answer 1

\[ \mu = \frac{\text{Velocity of light in vacuum}}{\text{Velocity of light in the material}} \]

\[ \therefore \ 1.33 = \frac{3 \times 10^{8} \ \mathrm{ms^{-1}}}{\text{Velocity of light in the material}} \]

\[ \therefore \ \text{Velocity of light in the material} = \frac{3 \times 10^{8}}{1.33} \]

\[ = 2.25 \times 10^{8} \ \mathrm{ms^{-1}} \]