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Finding frequency & wavelength

  1. Nov 28, 2009 #1
    1. The problem statement, all variables and given/known data
    Find the frequencies and wavelengths (in air) of these notes.
    A(440.0 Hz)
    C(523.3 Hz)
    the given frequencies are not the answers


    2. Relevant equations
    velocity=frequency*wavelength


    3. The attempt at a solution
    343m/s=440Hz/wavelength
    wavelength=.780 m
    this isnt right, and i only have 5 chances for my online hw, so i didnt want to waste this equation on the the other problem

    i also have know idea how to find the frequency, if it's given, but it isnt right
     
  2. jcsd
  3. Nov 28, 2009 #2

    ideasrule

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    Homework Helper

    There's either missing information, or the problem doesn't make sense. How can the given frequencies not be the answers? What medium are the frequencies given FOR, if not air? Were any temperatures mentioned?

    BTW, your equation velocity=frequency*wavelength is correct. However, you then used 343 m/s=440Hz/wavelength in your solution, which is velocity=frequency/wavelength.
     
  4. Nov 28, 2009 #3
    This is what is says,
    The lowest note on a piano is A, four octaves below the A given in the table. The highest note on a piano is C, four octaves above middle C.
    Chromatic Musical Scale
    Note Frequency
    Middle C 261.7
    C#(C-SHARP) D^b(D-flat) 277.2
    D 293.7
    D#, E^b 311.2
    E 329.7
    F 349.2
    F#,G^b 370.0
    G 392.0
    G#,A^b 415.3
    A 440.0
    A#,B^b 466.2
    B 493.9
    C 523.3
     
  5. Nov 28, 2009 #4

    Redbelly98

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    Staff Emeritus
    Science Advisor
    Homework Helper

    It sounds like you are to use the frequency that is 4 octaves below 440 Hz, rather than 440 Hz itself.
     
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