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## Homework Statement

A 45 kg figure skater is spinning on the toes of her skates at 1.0 rev/s. Her arms are outstretched as far as they will go. In this orientation, the skater can be modeled as a cylindrical torso (40 kg, 20 cm average diameter, 160 cm tall) plus two rod-like arms (2.5 kg each, 66 cm long) attached to the outside of the torso. The skater then raises her arms straight above her head, where she appears to be a 45 kg, 20 cm diameter, 200 cm-tall cylinder.

## Homework Equations

Conservation of angular momentum

Moment of Inertia

## The Attempt at a Solution

L

_{i}= (I

_{b}+ 2(I

_{a}))w

_{i}

w

_{i}= 6.2831 rad/s

I

_{b}= (1/2)(40)(.1)(.1)

I

_{a}= (1/3)(2.5)(.66)

^{2}

L

_{f}= (I

_{f})(w

_{f})

I

_{f}= (1/2)(45)(.1)

^{2}

L

_{i}= L

_{f}

Solve for w

_{f}

w

_{f }= (.926)(6.2831)/(.225)

Any ideas where I went wrong?