1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Fundemental Frequency units?

  1. May 13, 2009 #1
    1. The problem statement, all variables and given/known data
    The fundamental vibrational frequency of gaseous 14N16O is 1904 cm-1.

    a. Calculate the force constant, using the simple harmonic oscillator model


    2. Relevant equations

    K=u((2pi)(v))^2 u=reduced mass

    3. The attempt at a solution

    u=[(14)(16)/(30)] (1kg/6.02e^26)= 1.24e^-26 Kg/molecules

    K=(1.24e^-26 kg)((2pi)(1904 cm^-1))^2= 1.77e^-22 kg m^2

    How do I get the answer in N/m ??
     
  2. jcsd
  3. May 13, 2009 #2

    Matterwave

    User Avatar
    Science Advisor
    Gold Member

    What does it mean when there is a frequency given in cm-1? Frequency should be given in Hz (or per time of some sort). Perhaps instead of "fundamental frequency" they meant "wave number/vector"?
     
  4. May 13, 2009 #3
    cm^-1 is the wavenumber.
     
  5. May 13, 2009 #4

    Matterwave

    User Avatar
    Science Advisor
    Gold Member

    If you have K = u(2pi*v) why are you plugging in your wave number for v? v is a frequency yes? So how do you convert a wave number into frequency?
     
  6. May 14, 2009 #5
    Ok...

    Good point, I will change wave number to frequency.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Fundemental Frequency units?
  1. Units ? (Replies: 4)

Loading...