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A uniform 2-kg solid disk of radius ? = 0.4 m is free to rotate on a frictionless horizontal axle through its center. The disk is initially at rest, and then a 10-g bullet traveling at 580 m/s is fired into it as shown in the figure below. R/2 Part A If the bullet embeds itself in the disk at a vertical distance of 0.2 In above the axle, what will be the angular velocity of the disk? Express your answer in radians per second. ? W= 7.5 rad/s Submit Previous Answers Request Answer X Incorrect; Try Again; 19 attempts remainingPartA What is the initial angular momentum of the system? On an old-fashioned rotating piano stool, a woman sits holding a pair of dumbbells at a distance of 0.570 In from the axis of rotation of the stool. She is Express your asnwer in kilogram-meters squared per second. given an angular velocity of 2.90 rad/s , after which she pulls the dumbbells in until they are only 0.170 In distant from the axis. The woman's moment of inertia about the axis of rotation is 4.80 kg . m and may be considered constant. Each dumbbell has a mass of 4.65 kg and may be considered a point mass. Neglect friction. L = 25.8 kg . m /s in the direction of the motion For related problem-solving tips and strategies, you may want to view a Video Tutor Solution of Anyone can be a ballerina. Submit Previous Answers Request Answer X Incorrect; Try Again; 19 attempts remaining Part B What is the angular velocity of the system after the dumbbells are pulled in toward the axis? Express your answer in radians per second. rad/s Submit Request AnswerPart C On an old-fashioned rotating piano stool, a woman sits holding a pair of Compute the kinetic energy of the system before the dumbbells are pulled in. dumbbells at a distance of 0.570 In from the axis of rotation of the stool. She is given an angular velocity of 2.90 rad/s , after which she pulls the dumbbells in Express your answer in joules. until they are only 0.170 In distant from the axis. The woman's moment of inertia about the axis of rotation is 4.80 kg . In and may be considered constant. Each dumbbell has a mass of 4.65 kg and may be considered a point mass. Neglect friction. For related problem-solving tips and strategies, you may want to view a Video K = Tutor Solution of Anyone can be a ballerina. Submit Request Answer Part D Compute the kinetic energy of the system after the dumbbells are pulled in. Express your answer in joules. O ? K = Submit Request AnswerReview | Constant Part A A hollow spherical shell with mass 2.35 kg rolls without slipping down a 40.0 0 slope. Find the acceleration of the shell. For related problem-solving tips and strategies, you may want to view a Video Tutor Solution of Express your answer in meters per second squared. A rolling bowling ball 4 = 3.78 m/s2 Submit Previous Answers Correct Set Up: Let + be down the incline and let the shell be turning in the positive sense of rotation. Apply EF = wid to the translational motion of the center of mass and Ev = Jo to the rotation about the center of mass. The free-body diagram for the shell is given in the figure below. From Table 9.2. Iam = } m.R2. ing sin B mycase Solve: EF, = ma, gives mg sin 8 - f = mac. Er = la gives fR = (mR? )a With a = com/ R this becomes f = ma.- Combining the equations gives my sin B - ma. = mac and Cem = 3g sim 3(9.80 m/s )(sin 40.0") 5 -= 3.78m/s2Part D hollow spherical shell with mass 2.35 kg rolls without slipping down a 40.0 * slope or related problem-solving tips and strategies, you may want to view a Video Tutor Solution of If the mass were doubled to 4.70 kg . find the acceleration of the shell. rolling bowling ball Express your answer in meters per second squared. ROB ? 0.34 Submit Previous Answere Request Answer * Incorrect; Try Again; 19 attempts remaining Part E If the mass were doubled to 4.70 kg . find the friction force on it. Express your answer in newtons. F = 0.34 N Submit Previous Aneware Request Answer X Incorrect; Try Again; 19 attempts remainingPart A A light rope is wrapped several times around a large wheel with a radius of 0.385 m. The wheel rotates on frictionless bearings about a stationary horizontal axis, as shown in the figure (Figure 1). The free end of the rope is tied to a suitcase with a mass of 14.5 kg. The suitcase is Calculate the angular velocity of the wheel when the suitcase reaches the ground. eleased from rest at a height of 4.00 m above the ground. The suitcase has a speed of Express your answer in radians per second. 3.85 m/s when it reaches the ground. FORFEMA Mdo for Part ( redo folkart A reGainfor Part A keyboard shortcuts for Part A help for Part A rad/s Submit Request Anewer Part B Calculate the moment of inertia of the wheel. Express your answer in kilogram meters squared. or Part B M.to for Part ( rado for part B reor Part E keyboard shortcuts for Part B help for Part B Figure