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Harmonic Oscillator and Total Energy

  1. Mar 27, 2013 #1
    Okay, so if a harmonic oscillator has a restoring force given by Hooke's Law such that

    Fs = -kx

    and its integral gives the potential energy associated with the restoring force:

    PE = -(1/2)kx2

    Then for the total energy of a harmonic oscillator, why is the TE:

    TE = Evibration + Erotation

    Instead of:

    TE = Evibration + Erotation - (1/2)kx2
  2. jcsd
  3. Mar 28, 2013 #2
    hookes law applies to everyday objects like a mass on a spring,
    I assume that when you speak of vibration and rotation energies you are considering a molecule?
    If so, then 1/2KX^2 = E vib + E rot
  4. Mar 28, 2013 #3


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    Staff: Mentor

    Because the ##kx^2/2## term is included in ##E_\mathrm{vibration}##.
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