Problem 12.2 Part A An 8.0-cm-diameter hard disk spinning at 7200 rpm can stop in 13 revolutions. What is the magnitude of the angular acceleration? Express your answer in radians per second squared. AEd rad/s2 Submit Request Ansue Part B How long does it take the disk to come to a halt? Express your answer with the appropriate units. HA At = Value Units Submit Request Answer Provide FeedbackProblem 12.3 Part A A ceiling fan with 87-cm-diameter blades is turning at 68 rpm Suppose the fan coasts to a stop 30 s after being turned off What is the speed of the tip of a blade 10 s after the fan is turned off? Express your answer with the appropriate units. HA Value Units Submit Request Answer Part B Through how many revolutions does the fan turn while stopping? N VO AEd 2 ? Number of revolutions Submit Request Answer Provide FeedbackPart A A 45-cm-long, 85 g rod rotates about an axle at one end of the rod At what angular velocity, in rpm, does the rod have 50 mJ of rotational kinetic energy? Express your answer in revolutions per minute. AEQ rpm Submit Request Answer Provide Feedback DELLPart A A 20 kg solid door is 220 cm tall, 91 cm wide What is the door's moment of inertia for rotation on its hinges? Express your answer in kilogram-meters squared kg - m Submit Request Answer Part B What is the door's moment of inertia for rotation about a vertical axis inside the door, 17 cm from one edge? Express your answer in kilogram-meters squared. IN VC kg - m? Submit Request Answer Provide FeedbackProblem 12.17 Part A A 12-cm-diameter DVD has a mass of 25 g What is the DVD's moment of inertia for rotation about a perpendicular axis through its center? Express your answer in kilogram-meters squared AEd kg . me Submit Request Answer Part B What is the DVD's moment of inertia for rotation about a perpendicular axis through the edge of the disk? Express your answer in kilogram-meters squared AEQ kg - m Submit Request Answer