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Physics/acceleration of charges and EM radiation


Hello.  I'm trying to understand why the acceleration of a charged particle would emit energy (in the form of electromagnetic radiation). I understand, from research on the internet, why there would be a transition region in the force fields that propagates outward, but why there is energy in this? Where does the energy come from, and is there less kinetic energy transferred to the accelerated particle because of this?

In case you are wondering where this question is coming from, my son is taking physics in middle school, and he asked me what the connection is between electric force fields, electricity, magnetism,  and electromagnetic waves.  Hopefully I was able to explain the rest of it correctly, but I got stuck on this point.  This is not a homework assignment, it is a question from a curious boy and mom.

Thank you for your time, this is a wonderful service!!!!!

That's a pretty deep level to get to if he's in middle school.  The fields themselves contain energy, proportional to the field squared for their density.  The energy is intrinsic, the emitted energy comes from the forces that are applied to it.  There's no direct relationship, the mass of the particle is also an intrinsic property.


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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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