Here's the breakdown:
* Speed of light in vacuum: This is a fundamental constant, denoted by 'c', and is approximately 299,792,458 meters per second.
* Speed of light in a medium: Light travels slower in any medium other than a vacuum. The speed depends on the medium's properties, such as its density and composition.
* Index of refraction (n): This is the ratio of the speed of light in a vacuum (c) to the speed of light in a medium (v):
* n = c / v
Key points to remember:
* The index of refraction is always greater than or equal to 1.
* A higher index of refraction means the light travels slower in that medium.
* For example, the index of refraction of water is approximately 1.33, meaning light travels about 1.33 times slower in water than in a vacuum.
Let me know if you'd like more information about the index of refraction or its applications!
