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Calculate Angular Frequency,

  1. Dec 11, 2011 #1
    1. The problem statement, all variables and given/known data

    I'm trying to caluclate the angular freequency, given that I've only been given various values for the problem.

    Radius 2.0 m, Force applied for 5 s = 94 N. 4 objects each at 90°, each weighing 19kg, and at 1.9m from the axis.

    From this, I've calulated the values of the the moment of inertia, and the total torque.

    I thought we may need angular frequency to get the momentum, so thought I'd start here.


    2. Relevant equations

    L = Iω

    3. The attempt at a solution

    Not sure how to get the frequency from the values I've been given. I know you guys dont give the answers, but tips would be helpful.
     
  2. jcsd
  3. Dec 11, 2011 #2

    rude man

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    Well, are the masses 1.9m or 2.0m from the axis?
     
  4. Dec 12, 2011 #3
    The disk radius is 2.0m, the masses are at 1.9m from the axis.
     
  5. Dec 12, 2011 #4

    rude man

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    I'm wondering what the point of giving the radius is. Did they specify any mass for the disc, or just the 4 masses?

    Where is the force applied?
     
  6. Dec 12, 2011 #5
    Force is applied tangently, to the rim, therefore at the 2.0 m. Ignore the mass of the disk.
     
  7. Dec 12, 2011 #6

    rude man

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    Ah, we progress.

    OK, so can you figure out how much torque is applied about the table axis during those
    5 seconds?
     
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