When light crosses from one medium to another of a different density, its speed and wavelength change. Where it strikes the new surface at an angle, the transmitted wave is refracted -- it changes direction.[br][br]More information:[br][url]http://poppersdreamland.blogspot.com/2012/02/snells-law-1.html[/url]

Drag L into the medium with a higher Index of Refraction to view reflected vector R.[br]The angle at which light fails to transmit due to the difference in density is the critical angle.[br][br][br]______[br][br][b]This is an old worksheet! Improved versions:[/b][br]Refraction: [url]http://www.geogebratube.org/material/show/id/112931[/url][br]Vector intersections: [url]http://www.geogebratube.org/student/b74031#chapter/761[/url][br][br][br]Light Properties (book) :[url]http://tube.geogebra.org/material/show/id/128472[/url]