# Question

A person stands on a platform, initially at rest, that can rotate freely without friction. The moment of inertia of the person plus the platform is lp. The person holds a spinning bicycle wheel with its axis horizontal. The wheel has moment of inertia lw and angular velocity ww. What will be the angular velocity wp of the platform if the person moves the axis of the wheel so the it points?

(a) Vertically upward,

(b) At a 60o angle to the vertical

(c) Vertically downward?

(d) What will wp be if the person reaches up and stops the wheel in part (a)?

(a) Vertically upward,

(b) At a 60o angle to the vertical

(c) Vertically downward?

(d) What will wp be if the person reaches up and stops the wheel in part (a)?

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