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Electromagnetic wave emission after source vanishes

  1. Jan 22, 2014 #1
    I'm reading about electromagnetic waves and I can't make sense of their self-sustaining nature. If a charge accelerates for a moment and then stops a disturbance in the electric field is sent out. This changing electric field creates a changing magnetic field and they continue to sustain each other, propagating infinitely outward. Now, if the source charge were to vanish there would still be a changing E/B field in its immediate vicinity which will continue to exist. Wouldn't this mean that the waves are emitted forever?
     
  2. jcsd
  3. Jan 22, 2014 #2
    Nevermind. Stupid question.
     
  4. Jan 22, 2014 #3

    davenn

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    no, not a stupid question

    Yes the EM wave continues to propagate outwards after the source stops emitting

    not really too different than if you throw a pebble into a pond, the initially generated waves will still radiate outwards, even tho new waves are not being created at the source

    Dave
     
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