10. The circle in the image to the right represents the path followed by an object moving at constant speed. At four different positions, the object's motion is depicted using velocity and acceleration vectors. Choose the labeled point where the depiction is correct. (A) Point A T (B) Point B C (C) Point C (D) Point D D Questions 11 and 12 refer to the image to the right, showing a block with an unknown 205 - mass being pushed on by a force equal to F = 260 N, applied to the box at an angle 20 degrees from horizontal. There is significant friction between the block and the F surface, which prevents the box from sliding. ? 11. The magnitude of the force of static friction acting on the block is most nearly... (A) 89 N (B) 244 N (C) 260 N (D) It cannot be determined 12. The coefficient of static friction between the box and the surface is most nearly... (A) 0.34 (B) 0.55 (C) 0.94 (D) It cannot be determined 13. A ballet student with her arms and a leg extended spins with an initial rotational speed of 1.0 rotation per second. As she draws her arms and leg in toward her body, her rotational inertia becomes 0. 80 kg - m and her rotational speed is 4.0 rotations per second. What was her initial rotational inertia? (A) 3. 2 kg . m (B) 0. 1kg . m (C) 12.8 kg - m (D) 0. 050 kg . m 14. A block is on a ramp, with no objects touching it other than the ramp. The block slides down the ramp at a constant velocity. This means that... (A) The ramp is frictionless (B) The magnitude of the force of friction is equal to the magnitude of the component of the weight acting parallel to the surface of the ramp (C) The magnitude of the force of friction is equal to the weight of the block D) The magnitude of the force of friction is equal to the magnitude of the normal force between the block and the ramp.15. An object consists of two concentric disks glued together. The smaller disk (the white disk in the image) has a radius R, while the larger disk has a radius of 2.R. A force F is applied tangent to the surface of the smaller disk, while another force of the same magnitude F is applied tangent to the surface of the larger disk. The net torque acting on the object is (A) 3RF (B) 2RF (C) RF F (D)O 9 (rad) Questions 16 and 17 refer to the graph shown to the right, showing the angular 2.0 position of a wheel as a function of tie. The wheel started from rest at f = 0 and accelerated at a constant rate over the 4.0 s time period shown 1.5 1.0 16. What would be the rotational speed of the wheel at t = 4.0 s? (A) 0.25 rad/s 0.5 (B) 0.50 rad/s (C) 0.75 rad/s It (s) 2 (D) 1.0 rad/'s 17. What is the rate of rotational acceleration during the 4.0 s time period? (A) 0.25 rad/s' (B) 0.50 rad/s (C) 0.75 rad/ (D) 1.0 rad/s 18. The image shows two blocks sliding on a frictionless surface. Eventually the smaller block catches up with the larger one, collides with it, and sticks. What 21% is the speed of the two blocks after the collision? 3 m (A) v /2 (B) 4v /5 (C) v (D) 5v /4 A 19. A roller coaster starts at the top of a hill and goes through a loop on a frictionless track, as shown to the right. Which D of the following best describes the magnitude of the car's velocity = 20m as it passes each point? (A) VA = VB = VC = VD b = 60m (B) VA VA = VC = VD (C) VA = VD = VC = VA (D) Not possible to tell with the given information B