Week 10: Interference/Diffraction Chapter 36 & 37

Facts you may need for the Final:
All of chapter 36 except 36.6.
In chapter 37 you should concentrate on sections 37-1, 37-2, 37-5, and the first part of 37-7.

Interference, in general.
Double slit and Diffraction grating interference.
Thin film interference.
Diffraction, in general.
Single slit, and circular aperature diffraction.

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Concept-tests:
10.1 Two-slit and polarization

10.2 Intensity and phase shift

10.3 Diffraction with different colors

10.4 Two-slit and glass slide

10.5 Thin film-gas on water

10.6 Huygens and EM waves

10.7 Diffraction of Sound

10.8 Squeaks and Diffraction


Answers to Concept Tests

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Demos:
DOUBLE SLIT AND DIFRACTION GRATING INTERFERENCE--demos performed with both green and red laser light. Constructive interference for the red laser occurs at larger angles (the pattern is more spread out) than for green light. Why?

BIG BUBBLE IN WHITE LIGHT--demonstrated thin film interference, where the thin film is the soap bubble. You see colors because only certain wavelengths constructively interfere depending on the thickness of the bubble at a particular location.

SINGLE SLIT DIFFRACTION--laser light shown through a narrow slit. When the slit width is decreased the light beam diffracts and spreads out.

HOLOGRAM--laser light illuminates the hologram. The hologram is made by interferening reflected light from the object with a reference beam. (It is like an interferometer with one mirror replaced by an object). The film records the interference pattern, when illuminated the film diffracts the light to reproduce a virtual 3D image of the object.

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Links:

Diffraction & Interference--check this page out. It is info for a class like ours...it's like looking into another world.

LIGO--you are paying for this interferometer designed to detect gravity ways. Find out what you are spending your money on.

holograms-- there are mucho many web pages on holograms, here is one of them.