16) When a rigid object rotates about a fixed axis, what is true about all the points in the object? (There could be more than one correct choice.) A) They all have the same tangential speed. By They all have the same tangential acceleration. c) They all have the same angular speed. D) They all have the same radial acceleration. E) They all have the same angular acceleration. 17 A croquet mallet balances when suspended from its center of mass, as shown in the left part of the figure. If you cut the mallet into two pieces at its center of mass, as shown in the right part of the figure, how do the masses of the two pieces compare?' (Assume the handle is uniform) A) The piece with the head of the mallet has the greater mass. By The piece with the head of the mallet has the smaller mass. C) The masses are equal. Dj It is impossible to tell. 18) As shown in the figure, a given force is applied to a rod in several different ways. In which case is the torque about the pivot P due to this force the greatest? 2. B) 2 9 3 D) 4 95 19) A figure skater is spinning slowly with arms outstretched. She brings her arms in close to her body and her angular speed increases dramatically. The speed increase is a demonstration of Ap conservation of energy: her moment of inertia is decreased, and so her angular speed must increase to conserve energy- B) Newton's second law for rotational motion: she exerts a torque and so her angular speed increases. Co conservation of angular momentumic her moment of inertia is decreased, and so her angular speed must increase to conserve angular momentum. D) This has nothing to do with mechanics, it is simply a result of her natural ability to perform