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Coherent waves?

  1. Jul 18, 2011 #1
    is it necessary ffor coherent waves to be of same frequency? bcoz everywhere i read its written dat they must have a constant phse difference. but cant they have frequencies dat are simple numerical multiples of each other?
    like 256 512
  2. jcsd
  3. Jul 18, 2011 #2


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    That depends on what you mean by coherent. Coherence just describes the correlation of the properties of waves. See here: http://en.wikipedia.org/wiki/Coherence_(physics [Broken])
    Last edited by a moderator: May 5, 2017
  4. Jul 19, 2011 #3
    i think yes.. being multiples makes waves beat at the frequency that is HCF of both the frequencies.
  5. Jul 19, 2011 #4


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    There is a constantly changing phase difference between a fundamental and second harmonic. 2πf radians per second, actually. It just happens that, every cycle of the fundamental, the phase is a whole number of cycles.
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