The speed of a light wave in a medium is inversely proportional to the index of refraction (n) of that
medium. The index of refraction is a measure of how much slower light travels in a particular medium
compared to its speed in a vacuum.
Mathematically, the relationship between the speed of light (v) in a medium and the index of refraction
(n) is given by:
v=c/n
where:
- v is the speed of light in the medium
- c is the speed of light in a vacuum (approximately 3 x 10^8 meters per second)
This equation shows that as the index of refraction increases, the speed of light decreases. This decrease
in speed occurs because light interacts with the atoms or molecules in the medium, causing it to slow
down.
It's important to note that the speed of light in a vacuum (c) is constant and is considered the maximum
speed at which information or energy can travel in our universe. The speed of light in different
materials, such as air, water, or glass, is always slower than the speed of light in a vacuum due to the
interaction of light with the atoms or molecules of the medium.