Refraction and Snell's Law

In the material we just reviewed, we saw that the refractive index change between two materials affects how the direction of a light ray changes. The law that describes this change is Snell's Law. It is similar to the law of refraction in that it describes the angles relative to the perpendicular at the interface. But it differs in that this law refers to transmitted light and not to reflection. Also, the outgoing angle is usually different from the incoming angle. When light hits an interface between two media, there is typically a partially reflected ray as well – and that reflection still obeys the law of equal incident and outgoing angles.

Watch this video, which shows different ways of writing Snell's Law, either with or without making use of the wave speeds directly.

Last modified: Monday, August 30, 2021, 5:11 PM