Human rotational energy. A dancer is spinning at 72 rpm about an axis through her center with her arms outstretched, as shown in Figure 9.37. From biomedical measurements, the typical distribution of mass in a human body is as follows:
Figure 9.37 Problem 62.
Head: 7.0%
Arms: 13% (for both)
Trunk and legs: 80.0%
Suppose you are this dancer. Using this information plus length measurements on your own body, calculate (a) your moment of inertia about your spin axis and (b) your rotational kinetic energy. Use the figures in Table 9.2 to model reasonable approximations for the pertinent parts of your body.
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