Question
In: Physics
A student sits on a freely rotating stool holding two dumbbells, each of mass 2.97 kg...
A student sits on a freely rotating stool holding two dumbbells, each of mass 2.97 kg (see figure below). When his arms are extended horizontally (Figure a), the dumbbells are 0.90 m from the axis of rotation and the student rotates with an angular speed of 0.759 rad/s. The moment of inertia of the student plus stool is 2.64 kg · m2 and is assumed to be constant. The student pulls the dumbbells inward horizontally to a position 0.307 m from the rotation axis (Figure b). Two figures depict a man holding a dumbbell in each hand while spinning on a rotating stool. In figure (a), the man's arms are fully extended so the dumbbells are far from his body. He is rotating with angular speed ωi. In figure (b), the man's arms are pulled in so the dumbbells are close to his body. He is rotating with angular speed ωf > ωi. (a) Find the new angular speed of the student. rad/s (b) Find the kinetic energy of the rotating system before and after he pulls the dumbbells inward. (Kbefore = __J ), (Kafter = __ J)
Solutions
genius_generous answered 1 year agoRelated Solutions
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N
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