Snells Law

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Snells Law

• Important points to consider
•  
• Use subscripts so you dont get confused about
  which n youre referring to.
•  
• Sketch the problem.
• Be sure your calculator is in degree mode.
• The ray of light is initially in the incident
  material and then moves into the refracting
  material.

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The Problem A ray of light, initially in water,
enters a transparent substance at an angle of 36o
to the normal. The refracted ray inside the
transparent material makes an angle of 24o. Find
the speed of light inside the transparent
material. Assume the interface between the water
and transparent material is horizontal.
Refracting Material
Material ? n Material 1.33
240
Interface
Water n water 1.33
Incident Material
360
Normal
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The speed of light, v, inside the material is
related to the index of refraction, n, of the
material
where c is the speed of light in a vacuum. So, we
need to solve for n material which we can find
using Snells Law
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So,