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Homework Help: Help with physics frequency

  1. Dec 20, 2009 #1
    1. The problem statement, all variables and given/known data

    The radio atenna for an AM station is a 75m high tower that is equivalent to lamda/4
    Another lamda/4 corresponds to the ground reflection. At what frequency does the station transmit?

    2. Relevant equations

    v=f times lamda?!?


    3. The attempt at a solution
    THe answer was 1MHz..which is 1000Hz!?
    hmm,, I don't get this..Please helP! Thanks
     
  2. jcsd
  3. Dec 20, 2009 #2

    ideasrule

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    Homework Helper

    Re: Frequency??

    If 75 m is 1/4 of lambda, what's lambda? Since v=f*lambda, what's f?
     
  4. Dec 20, 2009 #3
    Re: Frequency??

    how do I know v?? lamda is 300...
     
  5. Dec 20, 2009 #4
    Re: Frequency??

    What is the velocity of radio waves (EM radiation)?
     
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