A ballerina begins a tour jeté (Fig. 11-19a) with angular speed ωi and a rotational inertia consisting of two parts: Ileg = 1.44 kg·m2 for her leg extended outward at angle θ = 90.0° to her body and Itrunk = 0.660 kg·m2 for the rest of her body (primarily her trunk). Near her maximum height she holds both legs at angle θ = 30.0° to her body and has angular speed ωf (Fig. 11-19b). Assuming that Itrunk has not changed, what is the ratio ωf/ωi?
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