Generating Electromagnetic Waves

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Electromagnetic waves are generated by charged particles accelerating, creating changes in electric and magnetic fields as described by Maxwell's equations. A permanent magnet generates its magnetic field through the spin of electrons, but moving the magnet does not typically produce electromagnetic waves efficiently. The discussion highlights that while a permanent magnet can influence electromagnetic fields, it is primarily electric charges that are the source of electromagnetic waves. The example of a pulsar is noted, where waves are produced due to electrons being accelerated by a strong magnetic field. Overall, the conversation emphasizes the role of electric charges in generating electromagnetic waves, even when considering the effects of permanent magnets.
Caio Ferrari
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Every book I ever read describes a electromagnetic wave as a phenomena generated by charged particles accelerating. This will produce a change in electric field that induces a magnetic field.
But, due to Maxwell equations a change in magnetic field will also produce an electric field. So, if a hold a permanent magnet bar into an spring mass system, does it will produce an electromagnetic wave?
 
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How does the permanent magnet generate its magnetic field? With charged electrons and their spin.
How do you change the magnetic field? By accelerating the object with its charges ;).

Moving a permanent magnet up and down should produce electromagnetic waves, probably with a terrible efficiency.
 
So, even a magnetic field is generated by a charged particles accelerated. That's ok.
It means that the only source of electromagnetic waves is a electric charge.

But I've never seen a book or even a example in which a wave is produced by a permanent magnet. Even a pulsar produces its waves because the electrons are being accelerated by a very strong magnetic field.
 
I'm working through something and want to make sure I understand the physics. In a system with three wave components at 120° phase separation, the total energy calculation depends on how we treat them: If coherent (add amplitudes first, then square): E = (A₁ + A₂ + A₃)² = 0 If independent (square each, then add): E = A₁² + A₂² + A₃² = 3/2 = constant In three-phase electrical systems, we treat the phases as independent — total power is sum of individual powers. In light interference...

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