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Find the total mechanical energy.

  1. Nov 1, 2006 #1
    Good day,
    I found this question on the Web.

    A piston in an engine moves back and forth over a distance of 2mm in SHM with a frequency of 120Hz. Find the total mechanical energy.

    Is there a way to find the energy without knowing the piston's mass?
    The answer provided is [tex]14 \mu~J[/tex]

    Many thanks,
  2. jcsd
  3. Nov 1, 2006 #2

    Doc Al

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    I don't see how--the energy would be proportional to the mass (given fixed frequency and amplitude). Perhaps the mass is given elsewhere.
  4. Nov 1, 2006 #3


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    I don't see how. The total energy is [itex] {1 \over 2} m \omega^2 A^2 [/itex].
  5. Nov 1, 2006 #4


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    I've been looking for a way to do it without the mass and I can't see it....
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