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Homework Help: Rotational Dynamics Problem

  1. Oct 21, 2004 #1
    Here's the problem:

    diameter = 3.45 cm
    angular speed = 11.4 rad/s
    angular deceleration = -.96 rad/s

    How far does the coin roll before coming to a stop?

    How would I set this problem up? Thanks!
     
  2. jcsd
  3. Oct 21, 2004 #2

    Pyrrhus

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    Homework Helper

    Remember

    [tex] v = r \omega [/tex]

    [tex] a = r \alpha [/tex]
     
  4. Oct 21, 2004 #3
    Reply

    thanks for the reply.
    ok, I converted 3.45 cm to m = .0345 m
    then, I got the linear velocity = 11.4 x .0345 = .3933 m/s
    next, I got the linear acceleration = -.96 x .0345 = -.03312 m/s^2

    ok, I plug all of this into a kinematics equation and get 5.94 m, does this sound right? Thanks!
     
  5. Oct 21, 2004 #4
    r is radius....you must change the diameter to radius
     
  6. Oct 21, 2004 #5
    reply

    dang, I did that the first time I tried this..lol. ok let me reattempt this.
     
  7. Oct 21, 2004 #6
    I get the same exact thing.
     
  8. Oct 22, 2004 #7
    Reply

    Anyone.....?
     
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