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10 videos · 4 h 33 min
Explainer · YouTube
Khan Academy
A clear, chaptered walk through almost exactly what this session covers: how emission depends on frequency, the threshold, why intensity changes only the number of electrons, why the wave model fails, and how photons of energy hf fix it, ending with the photovoltaic effect behind solar cells. Watch for the moment intensity and frequency part ways; it is the heart of the lesson.
Lecture · YouTube
Physics Explained
How the light quantum was really born: not from the photoelectric effect, but from Einstein's 1905 thermodynamic argument about blackbody radiation, running from Wien's law and Boltzmann's entropy to the photoelectric equation and Millikan's confirmation. The perfect bridge between the last chapter and this one.
Explainer · YouTube
FloatHeadPhysics
A story-driven history from 'The tiny lab accident' to 'Einstein's epiphany' (16:14). The jump starts at the chapter 'Lenard's trigger hypothesis' (7:27), the classical rescue in which light merely releases electrons that already carry their energy, followed by 'Trigger hypothesis is in trouble' (9:03): section 3's failures, told as a story. Rewind to 0:00 for the discovery chapters.
Explainer · YouTube
Dr. Jorge S. Diaz
Physicist Jorge Diaz's detailed presentation of how Millikan tested Einstein's light theory. Read it against section 5: the straight line of stopping potential against frequency, its slope h/e, and Millikan accepting the equation long before he accepted the photon.
Demo · YouTube
Looking Glass Universe
Mithuna Yoganathan measures Planck's constant at home with coloured LEDs, turning the voltage down until each one just goes dark. That is section 6's 1240 rule run in reverse: each electron crossing the LED gives up about e·V to make one photon, so the turn-on voltage in volts is roughly 1240 divided by the wavelength in nanometres. Her description says the experiment proves light is a particle; read Part 7's fine print before taking that literally.
Explainer · YouTube
Veritasium
Veritasium visits the US Navy to try the best night-vision goggles in the world and explains how they work. Map what you see onto section 7's chain: a photocathode turns photons into electrons by the photoelectric effect, a microchannel plate multiplies them, and a phosphor screen turns them back into light.
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.
Explainer · MIT
MIT OpenCourseWare
Barton Zwiebach takes on the photoelectric effect in MIT's 8.04 Quantum Physics I (Spring 2016). Expect a university-level blackboard treatment; watch it after the lesson, with Einstein's equation from Part 4 and the stopping-potential graph from Part 5 in mind.
Demo · Institute of Physics
Institute of Physics
A three-minute classroom demonstration from the Institute of Physics and the National STEM Learning Centre: a zinc plate on a gold-leaf electroscope, lit with ultraviolet. This is the bench from the hook and Hallwachs's 1888 experiment; watch the leaves and keep in mind that only a negatively charged plate loses its charge.
Lecture · Nobel Prize
Nobel Prize · Ferenc Krausz
Ferenc Krausz's Nobel lecture, 'Attosecond physics: exploring sub-atomic motions', given on 8 December 2023. His group made the 2010 neon measurement in this section's callout; watch for how attosecond pulses clock electron motion, the kind of stopwatch needed to time photoemission at all. Advanced, and only partly about photoemission.