Thin Film Interference
The applet:
http://webphysics.davidson.edu/physlet_resources/bu_semester2/c26_thinfilm.html
The explanation:
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In your textbook, look through Section 24-8.
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http://www.screencast.com/t/e0AYdylu
Make a list of some phenomena that are caused by thin-film interference.
In your textbook, look at diagrams 24-20 and 24-32.
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What two differences account for whether the reflected light is reinforced or cancelled?
Watch the video at http://www.screencast.com/t/e0AYdylu to learn how the Thin-Film Applet works.
Use the Thin-Film Applet at http://webphysics.davidson.edu/physlet_resources/bu_semester2/c26_thinfilm.html to do
the following:
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Find out whether the top reflection is upright or inverted.
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Find out whether the bottom reflection is upright or inverted when:
o The layer below has a higher index than the layer above.
o The layer below has a lower index than the layer above.
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Find out whether a ½ λ layer changes the phase of the top reflection relative to the bottom reflection when
o The layer below has a higher index than the layer above.
o The layer below has a lower index than the layer above.
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Find out whether a ¼ λ layer changes the phase of the top reflection relative to the bottom reflection when
o The layer below has a higher index than the layer above.
o The layer below has a lower index than the layer above.
Will all colors of light cancel for the same thickness?
Why does thin-film interference sometimes create a “rainbow” of colors?