Figure I for each arm, as a thin rod rotating at the end.
Then angular mmentum=I1*angle1/time1+ I2*angle2/time2
In a long jump, an athlete leaves the ground with an initial angular momentum that tends to rotate his body forward, threatening to ruin his landing. To counter this tendency, he rotates his outstretched arms to "take up" the angular momentum. In 0.393 s, one arm sweeps through 0.959 rev and the other arm sweeps through 0.336 rev. Treat each arm as a thin rod of mass 4.0 kg and length 0.60 m, rotating around one end. In the athlete's reference frame, what is the magnitude of the total angular momentum of the arms around the common rotation axis through the shoulders?
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