Quantum
Mechanics
Hipothesis of "quanta",
introduced by Planck, was found useful by Einstein for
explnation of the photoelectric effect and for studies of
hydrogen spectra. Almost, almost, without wave
machanics
Black-body
emission spectrum (lamp filament at 3000 K) (more here)
Franck-Hertz experiment
Spectrum
of an "energy-saving" lamp - quantification of energy
levels in atoms
links, sources, photo, more
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