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Homework Help: Natural vibration - energy method

  1. May 6, 2010 #1
    1. The problem statement, all variables and given/known data

    the problem is in the attached file, im having trouble with part d and e. cheers. [the answer for B is mr^2(0.5-16/9pi^2)]

    2. Relevant equations



    3. The attempt at a solution

    i wont upload all my working as i have stuff everywhere but for part d:

    i got my answer as 0.5I*(omega^2) + 0.5*m*(r*theta^2+(4r/3pi)^2), using the formula for total kinetic energy as 0.5Iomega^2+0.5mv^2

    and part e: mgR(theta.sintheta + costheta - 1)

    are these along the right tracks?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     

    Attached Files:

  2. jcsd
  3. May 12, 2010 #2
    are you sure your question 3 is correct?
     
  4. May 12, 2010 #3
    im not too sure what you mean question three sorry, if by part C, then i'm not too concerned about that for the moment, just part D and E
     
  5. May 12, 2010 #4
    sorry... i mean D
     
  6. May 12, 2010 #5
    i have no idea if either of my answers for d or e are right, hence why i stuck it on here....im just so confused haha
     
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