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Rotating disk

  1. Oct 11, 2015 #1


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    1. The problem statement, all variables and given/known data
    The 29.5cm diameter disk rotates counterclockwise on an axle through its center. F1=20.8N, F2=58.6N, F3=58.6N, F4=20.8N, and d=5.27cm. What is the net torque about the axle? Let the counterclockwise direction be positive.
    2. Relevant equations
    Torque = force (perpendicular) x distance (from pivot point)

    3. The attempt at a solution
    F1 = 0 N*m
    F2 = 58.6 N x 0.1475m = -8.6435 N*m (clockwise)
    F3 = 0.0527m x 58.6 sin45 N = 2.627777283 N*m (counterclockwise)
    F4 = 0.0527m x 20.8 N = 1.09616 N*m (counterclockwise)
    Therefore torque is -4.9196 N*m.
    However that is apparently not the answer... What am i doing wrong? :/

    Attached Files:

  2. jcsd
  3. Oct 11, 2015 #2


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    check.. F3 = 0.0527m x 58.6 sin45 N = 2.627777283 N*m
  4. Oct 11, 2015 #3


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    Homework Helper

    Everything is correct, you miscalculated something. sin(45)?
  5. Oct 11, 2015 #4


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    I had my calculator in radians... Thank you guys :/
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