Free Response Period: Question 1 (7 points) An ice skater starts his performance-ending spin with his arms outstretched, rotating at 2.5 rev/s. As he pulls his arms inward, his rotational inertia decreases to 0.70 of its original value. Two students are discussing how to determine his final angular speed. Anna: "I think we have to use conservation of angular momentum. The distance from the skater's center of mass to the axis of rotation decreases as he pulls his arms inward. The total moment of inertia goes down, and so the angular velocity has to go up.' Noah: "Well, I agree that the angular velocity goes up but I think you are going to get the wrong value. We need to use conservation of energy instead of conservation of momentum because there is no collision here. The rotational kinetic energy is what's going to stay the same here, and as the moment of inertia decreases, the angular velocity goes up." (a) Which, if either, of these students do you agree with and think is correct? Justify your answer. (b) What is the skater's final angular speed? AP* Physics 1: Rotation and Angular Momentum (c) What is the ratio of the skater's final kinetic energy to his initial kinetic energy