September 15, 1998

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September 15, 1998
Models of the Universe Laws of Nature Earth
Centered Aristotle, Ptolemy Earth, Water, Air,
Fire.. Falling Cycles in cycles Sun Centered
Coepernicus, Keplers Empirical
Laws Ellipses, Areas, Periods Galileos
Experimental Laws Inertia, Falling
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September 15, 1998 2
Motions in Our Solar System Sun, Earth Moon
Periods Sun around galaxy Stars around
earth... Earth around sun, spin, seasons Phases
of moon, planets Simulating Motion...
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September 15, 1998 3
Models of the Atom Dalton - combinations of
atoms Balmer - spectrum of hydrogen (l) Thomson
- discovery of electron Planck - photon energy
(E h f) Rutherford -planetary model Bohr -
physics of planetary model deBroglie - electron
is wave Shrodinger - quantum model
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September 15, 1998 4
Dalton measured masses of atoms by weights
of molecules made from combinations of
atoms. For example if ......N2O
4.0 ..NO 2.5 .NO2 3.5 then N ____,
O _____
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September 15, 1998 5
Balmer analyzed Spectrum of Hydrogen
6.6 4.9 4.3 x 10-7 meters
1 / l R ( 1 / n2 - 1 / 12 )
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September 15, 1998 6
Thomson . Discovered electron in 1895
e e e e e e
e
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September 15, 1998 7
Bohr