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Homework Help: Is this possible?

  1. Dec 7, 2006 #1
    A bugle is essentially a 2.65m pipe that is open at both ands. Determine the lowest frequency notes that can be played on a bugle.

    Is this question possible? after using every equation learned to my knowledge, i could find no way to determine the frequency.

    Thank you

    remember the formulas v=f(lambda) Ln=nlambda/2 for open tube and v=331 +.59(T)

    i found wavelength without a problem which turns out to be 5.3m, but how do i find frequency of this? is it possible?
    Last edited: Dec 7, 2006
  2. jcsd
  3. Dec 7, 2006 #2

    Doc Al

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    Start by finding the wavelength of the lowest frequency (which is the largest wavelength) standing wave that will fit into that pipe. Hint: Where are the nodes and antinodes?

    Once you have the wavelength, use the relationship between speed, frequency, and wavelength to find the associated frequency. What's the speed of sound?
    Last edited: Dec 7, 2006
  4. Dec 7, 2006 #3
    but, my friend, we do not have a temperature for sound to find its true velocity, therefore insn't it impossible to find the true frequency?

    we are not given the true velocity. yes i know it is 331m/s, but we are not given temperature to find the true frequency. the book has an answer of 64.9Hz if youd like to know
    Last edited: Dec 7, 2006
  5. Dec 7, 2006 #4


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    With a question like this you can just assume normal room temperature in which case the speed of sound is 344m/s.
  6. Dec 7, 2006 #5

    Doc Al

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    That's true. If you are not given enough information (such as temperature) to find an accurate speed of sound, then you must settle for a less accurate estimate of the frequency.

    Edit: Kurdt has the right idea! Just assume standard room temperature, which is nominally ~ 22 C.
    Last edited: Dec 7, 2006
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