Light Dispersion through a Glass Slab
Rock the slab using the mouse.
This applet shows a glass slab and two beams of light. The beam on the
left of the slab is white and the beam on the right is the broken up
version of the first beam into the seven colors of the rainbow.
Rock the slab, by clicking on it, and see the effect which various angles
of incident light have on the dispersion.