___3. An ice skater spins with arms fully extended. If she pulls her arms closer to her body then                (a) the kinetic energy increases                (b) the moment of inertia decreases                (c) the angular momentum remains constant                (d) all of these _____10. A wooden ball is tied by a light string to a rod. The ball is then rotated with the constant angular speed. What happens to its linear speed when the length of the string is doubled? a) doubled       b) reduced by half          c) tripled         d) remains the same

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A:

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