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Frequency and C

  1. Sep 13, 2007 #1
    Hi, I have wanted to ask someone this for so long, but I know its stupid.

    Is there a maximum frequency as a side effect of a maximum speed of light?
    Thinking of light as a pure wave and at a fixed amplitude, it is going to have to travel the distance dictated by the amplitude and frequency, and as the frequency increases, its going to have to travel faster to reach that amplitude.

    At infinite frequency, wouldn't the wave have to be at every amplitude at the same time?? This sounds impossible. It seems that the amplitude/frequency combination cannot result in a propagation speed faster than the speed of light. .

    Can someone clarify this and tell me where my mind is stuck lol
  2. jcsd
  3. Sep 13, 2007 #2
    Nope. The thing to understand is that light isn't a particle wobbling up and down. So amplitude is immediately irrelevant.
  4. Sep 13, 2007 #3
    well I'm aware of the dual nature of light as a particle/wave, although not too refreshed on it. But what does a frequency and amplitude mean to the light if it is not a particle??
  5. Sep 13, 2007 #4


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    In classical electromagnetism it's just a periodic oscillation in the strength of the electric and magnetic field vectors--see http://www.monos.leidenuniv.nl/smo/index.html?basics/light.htm [Broken], or look at the animated java applet here.
    Last edited by a moderator: May 3, 2017
  6. Sep 13, 2007 #5
    ok thanks, this helps. And thinking about it now, a 60 Hz light wave would actually have to propagate slower than a 1Hz light wave, with both traveling at C by my reasoning, and that makes no sense.
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