Ch 22 Reflection and Refraction of Light

Law of Reflection

The angle of incidence is equal to the angle of refraction

θi = θr

image from RPI

Specular Reflection vs. Diffuse Reflection

Specular reflection is the normal sort of reflection we observe from highly polished surfaces or commercial mirrors.
Diffuse reflection occurs when light is reflected off of irregular surfaces causing the reflection to not contain a clear image.
reflectionfigure2.jpgImage from Molecular Expressions

Check out JAVA tutorials from Molecular Expressions at


Different transparent mediums may have differing optical densities. The index of refraction of a medium is determined by
the ratio of the speed of light in a vacuum to the speed of light in the medium.

formula_n.gif VERY IMPORTANT... The frequency remains constant!!!

As the speed changes, so does the wavelength according the the universal wave equation.