10. A ballerina spins initially at 1.5 rev/s when her arms are extended. She then draws in her arms to her body and her moment of inertia becomes 0.88 kg · m^2, and her angular speed increases to 4.0 rev/s. What was her initial moment of inertia? [10 points]
Added by -Ngeles H.
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We know that angular momentum is conserved when there is no external torque acting on the system. So, we can write the conservation of angular momentum equation as: $$I_1 \omega_1 = I_2 \omega_2$$ Show more…
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