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Homework Help: Two Radio Transmitters, Interference, and Waves

  1. Feb 4, 2009 #1
    1. The problem statement, all variables and given/known data

    FM station KCOM ("All commercials, all the time") transmit simultaneously, at a frequency of 97.1 MHz, from two broadcast towers placed precisely 32.44 m apart along a north-south line.

    (a) What is the wavelength of KCOM's transmissions?

    2. Relevant equations

    velocity= (wavelength)(frequency)

    3. The attempt at a solution

    I can't even begin to fathom a way to do this problem. I've tried using the above equation: 343/97.1= 3.53. Which is the wrong answer. I'm not sure how to include the distance between the two transmitters.

    Can anyone help me?

    Thanks in advance!

  2. jcsd
  3. Feb 4, 2009 #2


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    Given the frequency, find the wavelength?
    Surely you have a formula relating frequency and wavelength for all waves.
  4. Feb 4, 2009 #3
    Yes, that is in my original posting. That isn't the answer.

    This invovles an interference. I'm not sure how the distance between the two transmitters relates.


    Edit to my original post: I realize that it is in MHz, and that the math in the first post is wrong. But 3.53E-6 is no where near the correct answer.
  5. Feb 4, 2009 #4


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    Terribly sorry, I missed reading that! Trying to answer too many questions at the same time I guess.

    In your calc L = v/f = "343/97.1= 3.53" you have used the speed of sound instead of the speed of radio waves, throwing your answer off by a large factor. Also, you forgot that the frequency was given in megahertz, so throw in a factor of 10^6 for that.
  6. Feb 4, 2009 #5
    Gar!! That's always my problem, using wrong numbers. I'm so sorry for all the trouble! Golly, one day that's really going to mess me up.

    Thanks so much for all the help. :)

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