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Help understanding EM waves

  1. Apr 14, 2010 #1
    Hello.

    Just a noob question about electromagnetic waves.
    An electron "wiggles" and sends out a change in electric field, which creates a change in magnetic field, which creates a change in electric field etc etc.

    My question is, because the photon travels to virtually infinite distances, does that mean the electric field of the electron is infinite? Or is it that the wavefront itself effectively extents the electric field indefinitely?

    Sorry if this question doesn't seem clear, not very good at getting a point across via text!

    Thanks in advance.
    Savy
     
  2. jcsd
  3. Apr 14, 2010 #2
    I think I know what you are asking so I will try to answer.

    Don't forget the time axis when talking about 'infinite'. Your electric and magnetic waves are plotted along the time axis, not a space one.

    Alternatively the wave reaches a certain distance form the origin after a certain time. Before this time there is no wave beyond this distance. This of course refers to the wavefront.
     
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