Concept explainers
A 9-kg uniform disk is attached to the 5-kg slender rod AB by means of frictionless pins at B and C. The assembly rotates in a vertical plane under the combined effect of gravity and of a couple M that is applied to rod AB. Knowing that at the instant shown the assembly has an angular velocity of 6 rad/s and an angular acceleration of 25 rad/s2, both counterclockwise, determine (a) the couple M, (b) the force exerted by pin C on member AB.
Fig. P16.91
Want to see the full answer?
Check out a sample textbook solutionChapter 16 Solutions
Vector Mechanics for Engineers: Statics and Dynamics
Additional Engineering Textbook Solutions
Mechanics of Materials, 7th Edition
DeGarmo's Materials and Processes in Manufacturing
Machine Tool Practices (10th Edition)
Applied Statics and Strength of Materials (6th Edition)
Introduction To Finite Element Analysis And Design
Thinking Like an Engineer: An Active Learning Approach (4th Edition)
- The 10-in.-radius brake drum is attached to a larger flywheel which is not shown. The total mass moment of inertia of the flywheel and drum is 22 lb ⋅ ft ⋅ s 2 and the coefficient of kinetic friction between the drum and the brake shoe is 0.41. Knowing that the initial angular velocity is 255 rpm clockwise, determine the force which must be exerted by the hydraulic cylinder at point B if the system is to stop in 85 revolutions. DO NOT ROUND OFF IN THE SOLUTION. ROUND OFF ONLY THE FINAL ANSWERarrow_forwardThe 10-in.-radius brake drum is attached to a larger flywheel which is not shown. The total mass moment of inertia of the flywheel and drum is 22 lb ⋅ ft ⋅ s 2 and the coefficient of kinetic friction between the drum and the brake shoe is 0.41. Knowing that the initial angular velocity is 255 rpm clockwise, determine the force which must be exerted by the hydraulic cylinder at point B if the system is to stop in 85 revolutions.arrow_forwardRequired information NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. A 4-kg slender rod is welded to the edge of a 3-kg uniform disk as shown. The assembly rotates about A in a vertical plane under the combined effect of gravity and of the vertical force P. Know that at the instant shown, the assembly has an angular velocity of 12 rad/s and an angular acceleration of 36.5 rad/s2, both counterclockwise. 120 mm Determine the force P. B The force P is D 240 mm с 240 mm (You must provide an answer before moving on to the next part.) |N.↓arrow_forward
- 5. AS-kg uniform disk is attached to the 3-kg uniform rod BC by means of a frictionless pin AB. An elastic cord is wound around the edge of the disk and is attached to a ring at E. Both ring E and rod BC can rotate freely about the vertical shaft. Knowing that the system is released from rest when the tension in the elastic cord is 15 N, determine (a) the angular acceleration of the disk, (b) the acceleration of the center of the disk. 150 mim C E B 75 mmA Darrow_forwardTwo uniform cylinders, each of mass m = 6 kg and radius r = 125 mm, are connected by a belt as shown. Knowing that at the instant shown the angular velocity of cylinder A is 30 rad/s counterclockwise, determine (a) the time required for the angular velocity of cylinder A to be reduced to 5 rad/s, (b) the tension in the portion of belt connecting the two cylinders.arrow_forwardThe 10-in.-radius brake drum is attached to a larger flywheel which is not shown. The total mass moment of inertia of the flywheel and drum is 22 lb ⋅ ft ⋅ s 2 and the coefficient of kinetic friction between the drum and the brake shoe is 0.41. Knowing that the initial angular velocity is 255 rpm clockwise, determine the force which must be exerted by the hydraulic cylinder at point B if the system is to stop in 85 revolutions. determine the force which must be exerted by the hydraulic cylinder at point B if the system is to stop in 85 revolutions. DO NOT ROUND OFF IN THE SOLUTION. ROUND OFF ONLY IN 2 DECIMAL PLACE IN THE FINAL ANSWER.arrow_forward
- Greek engineers had the unenviable task of moving large columns from the quarries to the city. One engineer, Chersiphron, tried several different techniques to do this. One method was to cut pivot holes into the ends of the stone and then use oxen to pull the column. The 4-ft diameter column weighs 12,000 lbs, and the team of oxen generates a constant pull force of 1500 lbs on the center of the cylinder G. Knowing that the column starts from rest and rolls without slipping, determine (a) the velocity of its center G after it has moved 5 ft, (b) the minimum static coefficient of friction that will keep it from slipping.arrow_forwardA slender homogeneous rod AB of mass m and length L is made to rotate at a constant rate w2 about the horizontal z axis, while frame CD is made to rotate at the constant rate w1 about the y axis. Express as a function of the angle 0 (a)the couple M1 required to maintain the rotation of the frame, (b) the couple M2 required to maintain the rotation of the rod, (C) the dynamic reactions at the supports C and D.arrow_forwardIf the earth were a sphere, the gravitational attraction of the sun, moon, and planets would at all times be equivalent to a single force R acting at the mass center of the earth. However, the earth is actually an oblate spheroid and the gravitational system acting on the earth is equivalent to a force R and a couple M. Knowing that the effect of the couple M is to cause the axis of the earth to precess about the axis GA at the rate of one revolution in 25 800 years, determine the average magnitude of the couple M applied to the earth. Assume that the average density of the earth is 5.51 g/cm 3 , that the average radius of the earth is 6370 km, and that ( Note: This forced precession is known as the precession of the equinoxes and is not to be confused with the free precession discussed in Prob. 18.123.)arrow_forward
- Each of the gears A and B has a mass of 675 g and a radius of gyration of 40 mm, while gear C has a mass of 3.6 kg and a radius of gyration of 100 mm. Assume that kinetic friction in the bearings of gears A, B C produces couples of constant magnitude 0.15 N.m, 0.15 N.m, 0.3 N.m, respectively. Knowing that the initial angular velocity of gear C is 2000 rpm, determine the time required for the system to come to rest.arrow_forwardTwo disks of the same material are attached to a shaft as shown. Disk A has a radius r and a thickness 2b, while disk B has a radius nr and a thickness 2b. A couple M with a constant magnitude is applied when the system is at rest and is removed after the system has executed two revolutions. Determine the value of n that results in the largest final speed for a point on the rim of disk B.arrow_forwardThe rotor of an electric motor has an angular velocity of 3600 rpm when the load and power are cut off. The 110-lb rotor, which has a centroidal radius of gyration of 9 in., then coasts to rest. Knowing that the kinetic friction of the rotor produces a couple with a magnitude of 2.5 1b.ft determine the number of revolutions that the rotor executes before coming to rest.arrow_forward
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY