Snell's Law
Two media of refractive indices n1 and n2 meet at a surface or interface. i incident angle and r is reflected angle
For air to dense medium we can simplify this equation by assuming refractive index in air is one (n1 = 1). Now we can simply write refractive index n
The speed of all electromagnetic radiation in vacuum is the same, approximately 3x108 meters per second, and is denoted by c. Therefore, if v is the phase velocity of radiation of a specific frequency in a specific material, the refractive index is given by
