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Homework Help: Car approaches Radio station

  1. May 13, 2010 #1
    1. The problem statement, all variables and given/known data

    The car is approaching a radio station at 25m/s. Broadcast frequency is 74.5 MHz.

    What change in frequency does the driver observe.

    2. Relevant equations

    Doppler effect on EM waves

    Fo = Fs (1 (+/-) u/c)

    u = speed of observer

    c = speed of light

    3. The attempt at a solution

    Got it ,, answer is 62.08 Hz
     
    Last edited: May 13, 2010
  2. jcsd
  3. May 13, 2010 #2

    berkeman

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    Staff: Mentor

    Definitely the Doppler Effect. Keep on reading a bit, and you'll see it addressed. Show us what you get for an answer!
     
  4. May 13, 2010 #3
    Are you sure? Because doppler effect was taught "last semester" in part one of this class. Which is why I am weary of using it... It's not sound frequency i don't think.
     
  5. May 13, 2010 #4

    berkeman

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    Staff: Mentor

    Well, what is the Doppler Effect (define it in your own words -- don't look up the definition yet)?

    And, what would be different if the source was a stationary whistle, instead of a radio station? What would be the same?
     
  6. May 13, 2010 #5
    The frequency is in MHz.. Would a doppler effect question be in MHz??
     
  7. May 13, 2010 #6
    Ok, I got it.. Found it,, haha Doppler effect on EM waves, Chapter 21.13.... Thank god for PDF books. I was only searching in chapters 26+ because all the questions prior to this one was pertaining.
     
  8. May 13, 2010 #7

    berkeman

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    Staff: Mentor

    Just to complete this learning module, please do a quick search on the Hubble Red Shift (at wikipedia or elsewhere). Do you see the theme?
     
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