Refraction and Polarization of Light

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Refraction and Polarization of Light 3/10/04

• Thursday group project and in-class exercises
• Friday Waves Particles
• Coming up on Friday March 26 Saturday March 27
• Physics Conference
• Nobel Laureate Leon Lederman (Fri. 8 pm)
• Student Poster Presentations

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Law of Reflection
angle of incidence angle of reflection
n1
n2
rfl
rfr
qrfl
qrfr
qi
Law of Refraction Snells Law
i
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Related Questions

• Where does the Law of Reflection come from?
• Why does light change speed in different media?
• Why does the frequency of light remain constant
  in different media?

Has to do with the electromagnetic nature of
light and the interaction of electromagnetic
radiation with matter ? the electric field
interaction with the electrons
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Electromagnetic Radiation Review Changing E ?
Changing B ? Changing E ? Changing B,
How to get these kinds of changing fields? ?
Accelerated charges
http//webphysics.davidson.edu/Applets/Retard/Reta
rd_FEL.html
Polarized vs. Unpolarized
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Re-Radiation Interference/Diffraction

• Reflection
• Changing speeds
• Polarization

Polarization ?Absorption ?Reflection (video
demo) ?Scattering (video demo)
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Not all wavelengths are equal Consider single
slit diffraction
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Different wavelengths interfere diffract re
fract scatter Differently
? dispersion ? rainbows!

• Scattering longer wavelengths diffract more
• ? bend around corners
• ? get around obstacles
• more than shorter wavelengths
• (video demo)