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Homework Help: Determing Revolutions

  1. Nov 29, 2011 #1
    Problem:
    A large fish strikes bait cast by a fisherman with a rod
    and reel. The fish creates tension in the line of 65 N.
    How many revolutions of the reel occur in 1.0 s if the
    reel has a moment of inertia of 4.0 * 10^-3 kg-m2 and the
    radial distance of the line from the reel’s axis is 4.0
    cm? Assume the reel has negligible friction.


    Solution:

    calculated Torque from tension force: 65N*.04m = 2.6

    ƩTorque = I*(angular Acceleration)
    2.6/ ( 4.0 10^-3) = angular Acceleration = 650

    (650)*(1sec) = Angular Velocity = 650 rad/sec * rev/(2pi) = 103 rev/sec.

    What am I doing wrong? the answer is 52 rev
     
  2. jcsd
  3. Nov 29, 2011 #2
    Sorry.... I just realized what I did wrong... I solved for ang velocity instead of theta....
     
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