University Quantum Mechanics I · Foundations of Quantum Mechanics · 1.05
de Broglie matter waves and electron diffraction
λ = h/p carried from photons to matter as h/√(2 m e V) for an accelerated electron, then tested through the Bragg condition against Davisson-Germer and Thomson ring angles, later neutrons and C60.
Course-map guide · not a complete lesson or simulationScope & orientation
What this subsection covers
λ = h/p carried from photons to matter as h/√(2 m e V) for an accelerated electron, then tested through the Bragg condition against Davisson-Germer and Thomson ring angles, later neutrons and C60.A strong response uses spectral radiance curves at three temperatures and states where the model stops being reliable.
Reasoning checklist
Evidence, assumptions and limits
Assumptions to state
State the system, observable, approximation, and conditions held fixed before using a model.
Evidence to collect
Does the stopping potential rise linearly with the frequency of the incident light, and does e times the slope of that line return h to within the uncertainty of the fit?
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Does the stopping potential rise linearly with the frequency of the incident light, and does e times the slope of that line return h to within the uncertainty of the fit? Useful evidence includes stopping potentials at five filtered frequencies, a least-squares fit of Vₛ against nu with residuals, h as e times the slope and phi as minus e times the intercept, both with propagated uncertainty, and reverse leakage named as a systematic.
Limits to state
This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus.
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This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus. It is a first dedicated quantum-mechanics course, distinct from University Physics V, which covers quantum mechanics alongside atomic, nuclear and particle physics in twenty units: this course is narrower, slower, and teaches the linear algebra it needs rather than assuming it. Hydrogen appears here as an introduction, with the full radial derivation belonging to a second course. A midterm examination is assumed around week 8. Follow your institution's published scope, notation, laboratory programme, and assessment rules. A result should be checked against units, signs, limiting cases, and the conditions under which its model was derived.
Diagram & examples
Work the claim before choosing an equation
Interactive concept map
Follow the model from claim to evidence.
λ = h/p carried from photons to matter as h/√(2 m e V) for an accelerated electron, then tested through the Bragg condition against Davisson-Germer and Thomson ring angles, later neutrons and C60. Non-relativistic, and single scattering assumed.
Model, evidence, and boundary
What is the strongest test of a claim about de Broglie matter waves and electron diffraction?
modelModel, evidence, and boundary turns the stated idea into a representation that can make a prediction.
Example questions
Try the reasoning before revealing the structure.
What is the strongest test of a claim about de Broglie matter waves and electron diffraction?
Quick check
Test the reasoning, not recall
What is the strongest test of a claim about de Broglie matter waves and electron diffraction?
Choose an answer to test the model.