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Physics/energy equations of two crucial experiments


Why the energy of photon radiation emitted by the electrons during their acceleration from relative rest to a certain velocity is ignored in the energy equations of both famous experiments devised a century ago for measuring the Planckís constant (Millikan in 1914, respectively Duane, Hunt and others in 1917-1920), and why the energy of bremsstrahlung emitted by the previously accelerated electron when they come again at relative rest is ignored in Millikanís experiment, although it is considered in the other experiment?

At the energies Millikan had available (mercury spark lamp), brehmsstrahlung radiation should've been singularly unimportant in the ejection of the electron from the metallic surface.  It's almost the opposite process from the Duane-Hunt measurement, which is at much higher energies and relies on brehmsstrahlung radiation to be made.  Also, all of the maximum-energy electrons are ejected for Millikan's experiment right from the surface, so there's really nothing for them to generate bremsstrahlung radiation in once they're in the vacuum.  It's not something that always happens the instant an electron is inside a metal, there's a statistical probability involved.  So the highest energy electrons will be faster than anything that lost energy that way, hence no need to correct for it.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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