Refraction across a flat surface (line).
When a ray of light crosses the surface of a translucent medium of different density, its speed and direction change (it is [i]refracted[/i]) according to Snell's Law.
In general, two rays result. A fraction of the light is reflected, and a fraction is transmitted into the new medium. Both rays are displayed according to their intensity.
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Reflection and Refraction
1. Reflect a ray: [url]http://www.geogebratube.org/material/show/id/111895[/url]
2. One side is reflective: [url]http://www.geogebratube.org/material/show/id/112443[/url]
3. Lamp: [url]http://www.geogebratube.org/material/show/id/112549[/url]
[b]→4. Refract a ray[/b]
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