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10 videos · 4 h 26 min
Lecture · Royal Institution
The Royal Institution · Sean Carroll · 2020
Sean Carroll tells the story from Planck and Einstein through Bohr, de Broglie and Schrödinger, then argues that the measurement problem is still open and makes his case for the many-worlds interpretation. Notice where the history ends and his interpretation begins.
Lecture · Center for Astrophysics
Center for Astrophysics · Donovan Moore
Donovan Moore, author of the biography 'What Stars Are Made Of', in a talk for the Center for Astrophysics, home of the Harvard College Observatory where Payne did the work. The jump lands on 'Starting the doctoral thesis', followed by 'A fundamental discovery' (22:13); rewind for her Cambridge years and the move to Harvard, far beyond the PBS Space Time briefing.
Explainer · YouTube
Khan Academy
A clear, chaptered tour of almost everything this session covers: discrete energy levels, the Bohr model and its energy-level diagram, excitation and de-excitation, hydrogen's spectrum, and how absorption lines identify the elements in distant stars. Its short look at orbital shapes previews chapter 16. Watch the energy-level diagram from about 5:37 and keep it in mind for the lab.
Explainer · YouTube
Physics Explained
A patient blackboard walk from Thomson's plum pudding and Rutherford's alpha scattering, through the instability of the nuclear atom, to Bohr's postulates, the quantization of angular momentum, the size of the atom, the energy levels and the visible hydrogen spectrum. Watch it after Part 5 and follow the algebra that turns L = nħ into Eₙ = −13.6 eV/n².
Explainer · YouTube
PBS Space Time
Matt O'Dowd tells how Cecilia Payne decoded stellar spectra in the 1920s and found that stars are made mostly of hydrogen and helium, against the expectations of the leading astronomers of her day. The perfect companion to Part 2.
Demo · Harvard
Harvard Natural Sciences Lecture Demonstrations
Kirchhoff and Bunsen's sodium-flame experiment in 85 seconds: sodium bicarbonate burning in a Bunsen flame puts a black line into the yellow of a continuous spectrum. Harvard's demo team note that it is a stand-in for the sodium part of the Sun's Fraunhofer spectrum and does not split the 589.0/589.6 nm pair, so expect one dark line, not two.
Explainer · YouTube
FloatHeadPhysics
A story-driven retelling of the alpha-scattering experiment, from the plum-pudding model through the results (9:15) to the planetary model (11:03), the first half of this section; watch for why a few large-angle bounces were enough to overturn the pudding atom. The video dates it 1911, the year Rutherford published his explanation, but Geiger and Marsden fired the shots in 1909.
Explainer · YouTube
Physics Explained
The calculation behind this section's death sentence for the planetary atom, done with classical physics alone: the electron's acceleration, the energy it radiates (the Larmor formula at 3:06), then a worked example. Check its result against the 1.6×10⁻¹¹ s quoted in the lesson.
Lecture · MIT
MIT OpenCourseWare · Donald Sadoway
Donald Sadoway's lecture 'Matter/Energy Interactions: Atomic Spectra' works through the Bohr model step by step: force balance (4:20), the Bohr radius (11:08), the ionization energy (18:11) and the electron's speed (23:12), all of this section's ladder. Keep going past 29:53, where Balmer enters and the lecture moves to transition energies (43:48), for Part 6.
Demo · Universitat de València
Laboratorio Física Cuántica Universitat de València
The 1914 Franck–Hertz experiment rebuilt in the University of Valencia's quantum-physics teaching lab, with mercury vapour as in the original, so it is the lesson's own example. Watch the anode current as the accelerating voltage rises: it drops sharply whenever the electrons carry just enough energy to excite a mercury atom, and the even spacing of the drops (6:24) is the rung the lesson puts at 4.9 eV.