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Generating Electromagnetic Waves

  1. Jun 26, 2012 #1
    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???
  2. jcsd
  3. Jun 26, 2012 #2


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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.
  4. Jun 26, 2012 #3
    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.
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