Chapters 29 Interference and Diffraction

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Chapters 29Interference and Diffraction
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Topics

• Huygens Principal
• Diffraction
• Interference
• two slit
• thin film
• Polarization
• Holography

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Huygens Principle
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Diffraction
http//ngsir.netfirms.com/applets/diffraction/2X/D
iffraction.htm
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Diffraction
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Interference
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Two Slit Interference
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Double Slit Interference
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Thin Film Interference
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Polarization
http//www.lon-capa.org/mmp/kap24/polarizers/Pola
rizer.htm
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Clicker Questions

• Consider plane waves incident upon a barrier with
  a small opening. After passing through the
  opening, the waves
• A) become polarized.
• B) continue as plane waves.
• C) fan out.
• D) converge.
• E) all of these
• 2) Waves diffract the most when their wavelength
  is
• A) long.
• B) short.
• C) Both diffract the same.
• 3) Colors seen when gasoline forms a thin film on
  water are a demonstration of
• A) interference.
• B) refraction.
• C) polarization.
• D) reflection.
• E) dispersion.

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Clicker Questions
4) The vibrational direction of the electron and
the plane of polarization of the light it A) are
the same. B) are at right angles to each
other. C) are independent of each other. D) may
or may not be at right angles to each other. 5)
An ideal Polaroid will transmit 50 of
unpolarized light incident on it. How much light
is transmitted by two ideal Polaroids that are
oriented with their axes parallel to each other?
A) between 50 and 100 B) 100 C) between
0 and 50 D) 50 E) 0