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Homework Help: Open organ pipe what does 6 beats per second mean?

  1. Jul 1, 2011 #1
    1. The problem statement, all variables and given/known data
    You are playing a note that has a fundamental frequency of 428 Hz on a guitar string of length 56 cm. At the same time, your friend plays a fundamental note on an open organ pipe, and 6 beats per seconds are heard. The mass per unit length of the string is 2 g/m. Assume the velocity of sound is 343 m/s.

    (a) What are the possible frequencies of the open organ pipe? (Enter your answers from smallest to largest.)

    (b)What is the length of the organ pipe?


    3. The attempt at a solution
    What does 6 beats per seconds mean?
    does it mean that there are 6 nodes?
     
  2. jcsd
  3. Jul 1, 2011 #2

    Ouabache

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    What happens when you play two notes close in frequency, notes that are almost but not equal in frequency?
     
  4. Jul 1, 2011 #3
    beats?
     
  5. Jul 1, 2011 #4

    Ouabache

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    Correct, also known as beat frequency. That is what you are hearing at 6 bps. To hear what is going on, you could listen to the 2nd (low frequency) audio example under http://en.wikipedia.org/wiki/Beat_%28acoustics%29" [Broken], towards the bottom of that page.
    To understand why you are hearing beats (and the mathematical relationship to the two contributing notes), you may want to look at http://hyperphysics.phy-astr.gsu.edu/hbase/sound/beat.html" [Broken].
     
    Last edited by a moderator: May 5, 2017
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