Today

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Todays agenda Review of Waves. You are
expected to recall facts about waves from Physics
1135. Youngs Double Slit Experiment. You must
understand how the double slit experiment
produces an interference pattern. Conditions for
Interference in the Double Slit Experiment. You
must be able to calculate the conditions for
constructive and destructive interference in the
double slit experiment. Intensity in the Double
Slit Experiment. You must be able to calculate
intensities in the double slit experiment.
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Youngs Double Slit Experiment
This experiment demonstrates the wave nature of
light. Consider a single light source, and two
slits. Each slit acts as a secondary source of
light.
Light waves from secondary slits interfere to
produce alternating maxima and minima in the
intensity.
Reference and toys fsu magnet lab, Colorado
light cannon, wave interference, double slit.
Interesting reading the double slit experiment
and quantum mechanics. But dont take it too
literally.
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How does this work?
Light waves from the two slits arriving at the
detection screen in phase will interfere
constructively
Light waves from the two slits arriving at the
detection screen in phase will interfere
constructively and light waves arriving out of
phase will interfere destructively. Another
applet (useful).
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In phaseconstructive.
Out of phasedestructive.
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How does this work?
Light waves from the two slits arriving at the
detection screen in phase will interfere
constructively and light waves arriving out of
phase will interfere destructively.
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Video, with some teasers about quantum mechanics.
You can find this video on Youtube. To avoid
streaming it, Ill play this in class.
Disclaimer! The video is part of an advertisement
for a New Age religion, and ends up heading
towards shaky ground. See, for example,
Schrödingers Cat One can even set up quite
ridiculous cases. A cat is penned up in a steel
chamber, along with the following device (which
must be secured against direct interference by
the cat) in a Geiger counter there is a tiny bit
of radioactive substance, so small, that perhaps
in the course of the hour one of the atoms
decays, but also, with equal probability, perhaps
none if it happens, the counter tube discharges
and through a relay releases a hammer which
shatters a small flask of hydrocyanic acid. If
one has left this entire system to itself for an
hour, one would say that the cat still lives if
meanwhile no atom has decayed. The psi-function
of the entire system would express this by having
in it the living and dead cat (pardon the
expression) mixed or smeared out in equal
parts.Erwin Schrödinger The idea of a
particle existing in a superposition of possible
states, while a fact of quantum mechanics, is a
concept that does not scale to large systems
(like cats), which are not indeterminably
probabilistic in nature.Wikipedia Electron
double slit applet.