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340 Hz note is played outdoors. Temperature and wave length

  1. Mar 23, 2007 #1
    1. The problem statement, all variables and given/known data

    A 340 Hz note is played outdoors on a day when the temperature is 25 degrees Celcius. What is the closest estimate of the wavelength of this note?

    A) .1 m
    B) 1 m
    C) 10 m
    D) 50 m
    E) 340 m

    2. Relevant equations

    http://www.artofproblemsolving.com/Forum/latexrender/pictures/e7d4b6d614f84b4b105ead162fa94e0d.gif [Broken]

    http://www.artofproblemsolving.com/Forum/latexrender/pictures/b9e251aca0bff9ace83197927124a406.gif [Broken]

    [PLAIN]http://www.artofproblemsolving.com/Forum/latexrender/pictures/0d2c032a601d8c290d422804dc30c00d.gif [Broken]
    might be useful

    3. The attempt at a solution

    basically, I tried looking for velocity relative to temperature.
    I used the previous equation that
    [PLAIN]http://www.artofproblemsolving.com/Forum/latexrender/pictures/0d2c032a601d8c290d422804dc30c00d.gif [Broken]

    but that didn't help much because I do not know m or k.
    I think I'm missing a basic knowledge because I have not learned much about this stuff yet. (I only know the formula...)

    someone help please!
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Mar 24, 2007 #2


    User Avatar
    Gold Member

    You're overthinknig the problem. They're trying to get you to understand as opposed to simply plug numbers in formulae.

    As a ballpark figure - how far will sound travel (in feet) in one second?
    How many wavelengths are we looking at in that second?
    Thus, how long is one wavelength (approximately).
  4. Mar 24, 2007 #3


    User Avatar
    Gold Member

    You should be able to find the speed of sound in air at various temperatures and pressures listed somewhere on the internet. You only need an approximate value and you already have the necessary equation.
  5. Mar 24, 2007 #4
    yes I figured this out. Sorry for not reposting. I found the velocity of sound at room temperature which is approximately 340.
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