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Mechanical Problem

  1. Jun 15, 2010 #1
    In the attachment is my problem.

    Attached Files:

  2. jcsd
  3. Jun 15, 2010 #2
    I don't think the bar will be in circular motion. The motion is rather complex since the string 1 is involved. And what is theta anyway? You haven't defined it yet.
  4. Jun 15, 2010 #3
    First of all, this question is not homework, Unknowingly was moved to this section!

    Thanks for reply
    Suppose string 1 is a solid and fixed bar; not a string actually :D, and on which the blue bar can freely rotate.

    As for theta, as I said, it's how many degrees the blue bar rotates after string 1 is cut, in other words, it's the angle between the negative x axis and the blue bar.

    Attached Files:

    • 11.PNG
      File size:
      779 bytes
    Last edited: Jun 15, 2010
  5. Jun 15, 2010 #4
    Use the law of energy conservation to find the relationship between angle theta and angular velocity, and then compute the integral to find angle theta w.r.t. time t. The integral is hard to compute, so use wolframalpha (http://integrals.wolfram.com/index.jsp) or any other tool. I believe the result won't look nice at all.
  6. Jun 15, 2010 #5
    hey this is a typical textbook problem.
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