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An adapted launcher uses a torsional spring about point O to help people with mobility impairments throw a Frisbee®. Just after the Frisbee® leaves the arm, the angular velocity of the throwing arm is 200 rad/s and its acceleration is 10 rad/s2; both are counterclockwise. The rotation point O is located 1 in. from the two sides. Assume that you can model the 2-lb throwing arm as a uniform rectangle. Just after the Frisbee® leaves the arm, determine (a) the moment about O caused by the spring, (b) the forces on the pin at O.
Fig. P16.86
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