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Chapter 25. Reflection and Refraction. Reflection and Refraction. Reflection. Reflection. We will focus on specular reflection. The Law of Reflection. All angles are measured with respect to the normal . normal. Multiple reflections. Snell’s Law of Refraction. Refractive Index.
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Chapter 25 Reflection and Refraction
Reflection We will focus on specular reflection
The Law of Reflection All angles are measured with respect to the normal. normal
Find the refractive index and the speed of light in the liquid
Find θair for the following cases: nwater = 1.33
Solution Total internal reflection
Total internal reflection (TIR) Total internal reflection occurs when θincident > θc
The critical angle, θc θc is the angle of incident θincident when θrefraction = 90o
Cubic Zirconium Refractive index: 2.15 to 2.18 (diamond: 2.42) Hardness: 8.5 to 9 (diamond: 10) Ingredients: zirconium oxide, magnesium, calcium (diamond: carbon)
Applications of TIR Fiberoptics
Huygen’s Principle Every point of a wave front may be considered the source of secondary wavelets that spread out in all directions with a speed equal to the speed of wave. The final wave is the sum of all these secondary wavelets.
Principle of Least Time Light always travels between two points in the path that takes the least amount of time.