Light - Index of Refraction

Question 1

index of refraction

Answer 1

• In previous lessons, we talked about the speed of light in a vacuum, c = 3.00*10^8 m/s. When light travels through a transparent medium other than vacuum, like air, water, or glass, it travels more slowly. Though it’s not always true, in general, the denser the medium, the slower light travels through it.
• So, in a given medium, light travels slower than in vacuum. The factor by which its speed is reduced is called the “Index of Refraction”, which has the symbol “n”.