Question: What is the refractive index of a medium if the speed of light in vacuum is 3 x 10^8 m/s and in the medium is 2 x 10^8 m/s?

Options:

1. 1.5
2. 0.67
3. 2.0
4. 1.0

Correct Answer: 1.5

Solution:

The refractive index n is calculated as n = c/v, which gives n = (3 x 10^8)/(2 x 10^8) = 1.5.