Modern Physics PC300

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Modern Physics(PC300)
Class 8 Quantum Mechanics Born
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Test Assessment
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Quantum Episode 6

• Episode 4 Charge
• Episode 5 Black Body - Quantized Radiation
• Photoelectric Effect
• All Earlier Episodes Classical Physics

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Photoelectric Effect
-

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Photoelectric Effect Intensity
Makes Sense more photons - more electrons
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Photoelectric Effect Frequency
Maximum KE does not depend on intensity
1902 Lenard -
1905 Lenard - Nobel Prize
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1905 Photoelectric Effect Solution
Classical electromagnetic theory has problems
explaining the independence of Kmax and light
intensity, the linear dependence of Kmax on light
frequency and the instantaneous (10-9s) response
of the photocurrent.
Einstein - Light composed of irreducible "grains"
- quanta (energy packets).
1921 Einstein - Nobel Prize
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Photoelectric Effect Work Functions
(Kmax)
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Various Work Functions
http//www.youtube.com/watch?vm55kgyApYrY
1923 Millikan - Nobel Prize
Why do different metals have different work
functions?
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(No Transcript)
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Sim 4 Photoelectric Effect
P-Drive\White\Modern Physics\Programs\Petutor\CTWI
NX Click on Photo15.ctb then hit OK
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Lab 6 Photoelectric Effect
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X Ray Production
1901 Roentgen - Nobel Prize
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EM Spectrum X-Rays
(Duane-Hunt Rule)
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Quantum Homework Questions

• Some PETUTOR Questions and an Electron Gun
  question
• Also
• Thornton and Rex

"Yeah, well I got mine first
Due Friday by 1000am
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1897 - J.J.Thompson
1906 - Nobel Prize
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X Ray Production
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Measuring charge/mass (e/m)
Electron beam Cathode Ray
Cathode Ray Tube
Derive in lab
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Lab ? - e/m setup
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1909 - Robert Millikan Precise Measurement of e
Oil Drop Experiment