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When a circus performer performing on the rings executes the iron cross, he maintains the position at rest shown in Figure P12.37a. In this maneuver, the gymnast’s feet (not shown) are off the floor. The primary muscles involved in supporting this position are the latissimus dorsi (“lats”) and the pectoralis major (“pecs”). One of the rings exerts an upward force
Figure P12.37
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Physics for Scientists and Engineers with Modern Physics
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