Difference between revisions of "Snell's Law"
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'''Snell's Law''' describes how the direction of [[light]] changes when it moves from one medium to another. | '''Snell's Law''' describes how the direction of [[light]] changes when it moves from one medium to another. | ||
| − | What Snell's Law says is that when light moves from a medium with a high index of refraction to a medium with a low index of refraction it will bend away the normal of the plane dividing the two media. Conversely, when light moves from a medium with a low index of refraction to a medium with a high index of refraction it will bend towards from the normal dividing the two media. | + | What Snell's Law says is that when light moves from a medium with a high [[index of refraction]] to a medium with a low index of refraction it will bend away the normal of the plane dividing the two media. Conversely, when light moves from a medium with a low index of refraction to a medium with a high index of refraction it will bend towards from the normal dividing the two media. |
The two forms of the law are: | The two forms of the law are: | ||
Revision as of 00:36, September 25, 2009
Snell's Law describes how the direction of light changes when it moves from one medium to another. What Snell's Law says is that when light moves from a medium with a high index of refraction to a medium with a low index of refraction it will bend away the normal of the plane dividing the two media. Conversely, when light moves from a medium with a low index of refraction to a medium with a high index of refraction it will bend towards from the normal dividing the two media.
The two forms of the law are:
- n1 sin(θ1) = n2 sin(θ2)
- v2 sin(θ1) = v1 sin(θ2)
where:
- n1 and n2 are the indices of refraction in media 1 and 2, respectively
- v1 and v2 are the velocities of light in media 1 and 2, and
- θ1 and θ2 are the angle from the normal of the plane dividing the 2 media and the ray.
The index of refraction of a material is inversely proportional to the speed of light in that material, i.e. light will move slower in a material with a high index of refraction than it will in a material with a low index of refraction.