Answer: Many of the elements in horizontal-bar exercises

Chapter , Problem 15

(choose chapter or problem)

Many of the elements in horizontal-bar exercises can be modeled by representing the gymnast by four segments consisting of arms, torso (including the head), thighs, and lower legs, as shown in Figure P8.15a. Inertial parameters for a particular gymnast are as follows: Segment Mass (kg) Length (m) rcg (m) I (kg ? m2) Arms 6.87 0.548 0.239 0.205 Torso 33.57 0.601 0.337 1.610 Thighs 14.07 0.374 0.151 0.173 Legs 7.54 0.227 0.164 Note that in Figure P8.15a rcg is the distance to the center of gravity measured from the joint closest to the bar and the masses for the arms, thighs, and legs include both appendages. I is the moment of inertia of each segment about its center of gravity. Determine the distance from the bar to the center of gravity of the gymnast for the two positions shown in Figures P8.15b and P8.15c.