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Questions about electromagnnetic wave: amplitude

  1. Jan 27, 2007 #1
    I'm having a little trouble understanding some of this. Here's a few things I dont understand:

    - are wave amplitude and frequency/wavelength correlated, or are they independent of each other? (I understand freq and length are correlated because the speed of light is constant) ... (my guess is that they are independent because i remember reading somewhere that radio signals are transmitted through changes in amplitude, so if the freq of a radio station is always the same then they cant be correlated?)

    - (and, if they are independent of each other) does the amplitude of an electromagnetic wave also have an impact on the amount of energy that the wave carries?
  2. jcsd
  3. Jan 27, 2007 #2
    Earlier today:
  4. Jan 27, 2007 #3


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    Gold Member

    Just to clarify something that may be confusing you. When the amplitude is changed. This is referred to as amplitude modulation or more commonly AM. When the frequency is changed, this is known as frequency modulation or FM. Radio signals can be transmitted by either of these. In AM, the amplitude is independent of the frequency. In FM, the frequency is independent of the amplitude.
  5. Jan 27, 2007 #4

    Gib Z

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    Homework Helper

    Umm In answer to your question, no there in no direct relation between amplitude and the wavelength.
  6. Jan 27, 2007 #5
    Thanks for the help :) . I'll do further reading on my own, i didnt know where to start. :)
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