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1. The speed of light in a glass

Refraction:

Wiki MarkupIt’s the change in direction of a [wave|http://en.wikipedia.org/wiki/Wave] due to a change in its [medium|http://en.wikipedia.org/wiki/Optical_medium]. It is essentially a surface phenomenon. This is most commonly observed when a wave passes from one [medium|http://en.wikipedia.org/wiki/Optical_medium] to another at any angle other than 90° or 0°.\[1\]of a wave due to a change in its medium. It is essentially a surface phenomenon. This is most commonly observed when a wave passes from one medium to another at any angle other than 90° or 0°. (#6.)
Explanation:

Refraction of [light|http://en.wikipedia.org/wiki/Light] is the most commonly observed phenomenon, but any type of wave can refract when it interacts with a medium, for example when [sound waves|http://en.wikipedia.org/wiki/Sound_wave] pass from one medium into another or when water waves move into water of a different depth\[1\]. With light, the speed in transparent medium is lower than in vacuum since light can travel in vacuum and doesn’t need a medium to travel.

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<ac:structured-macro ac:name="anchor" ac:schema-version="1" ac:macro-id="8c45823a2bc8b7ed-157eec01-4a674375-90c5846d-7fda1a281ff61c94ea6de119"><ac:parameter ac:name="">3.</ac:parameter></ac:structured-macro> 3. _Reflection and Its Importance_. (n.d.).  Retrieved December 10, 2012, from Physics Classroom: \[http://www.physicsclassroom.com/class/refln/u13l1c.cfm\]

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4. Total internal reflection. (2012, December 10). Retrieved December 10, 2012, from Wikipedia: http://en.wikipedia.org/wiki/Total_internal_reflection

5. Prism (optics). (2012, December 8). Retrieved December 10, 2012, from Wikipedia: http://en.wikipedia.org/wiki/Prism_%28optics%29

6. Refraction. (2012, December 6). Retrieved December 10, 2012, from Wikipedia: http://en.wikipedia.org/wiki/Refraction^{Image Modified}

1.http://en.wikipedia.org/wiki/Refraction

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