16.81 The shutter shown was formed by removing one quarter of a disk of 0.75-in. radius and is used to interrupt a beam of light emanating from a lens at C. Knowing that the shutter weighs 0.125 lb and rotates at the constant rate of 24 cycles per second, determine the magnitude of the force exerted by the shutter on the shaft at A. 16.82 A turbine disk weighing 50 lb rotates at a constant rate of 9000 rpm. Knowing that the mass center of the disk coincides with the center of rotation O, determine the reaction at O immediately after a single blade at A, of weight 2 oz, becomes loose and is thrown off. 16.83 The 80-lb tailgate of a car is supported by the hydraulic lift BC. If BC fails and the tailgate falls and hits the car with an angular velocity of 5 B Fig. P16.81 A

16.81 The shutter shown was formed by removing one quarter of a disk of 0.75-in. radius and is used to interrupt a beam of light emanating from a lens at C. Knowing that the shutter weighs 0.125 lb and rotates at the constant rate of 24 cycles per second, determine the magnitude of the force exerted by the shutter on the shaft at A. 16.82 A turbine disk weighing 50 lb rotates at a constant rate of 9000 rpm. Knowing that the mass center of the disk coincides with the center of rotation O, determine the reaction at O immediately after a single blade at A, of weight 2 oz, becomes loose and is thrown off. 16.83 The 80-lb tailgate of a car is supported by the hydraulic lift BC. If BC fails and the tailgate falls and hits the car with an angular velocity of 5 B Fig. P16.81 A

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

A 255-lbf block is suspended from an inextensible cable which is wrapped around a drum of 1.75-ft radius rigidly attached to a flywheel. The drum and flywheel have a combined centroidal moment of inertia 12 lb . ft . s 2 . At the instant shown, the velocity of the block is unknown directed downward. Knowing that the bearing at A is poorly lubricated and that the bearing friction is equivalent to a couple M of magnitude 65 lb .ft, determine the velocity of the block before it has moved 3.5 ft downward if at S2 speed is 13.5ft/s
The flywheel of a small punch rotates at 300 rpm. It is known that 1800 ft.1b of work must be done each time a hole is punched. It is desired that the speed of the flywheel after one punching be not less than 90 percent of the original speed of 300 rpm. (a ) Determine the required moment of inertia of the flywheel. (b) If a constant 25-1b.ft couple is applied to the shaft of the flywheel, determine the number of revolutions that must occur between each punching, knowing that the initial velocity is to be 300 rpm at the start of each punching.
1-The work done by weight is ? 2-Polar moment of inertia about B is ? 3-angular velocity at position 2 ?
6. A shaft with 3 metres span between two bearings carries two masses of 10 kg and 20 kg acting at the extremities of the arms 0.45 m and 0.6 m long respectively. The planes in which these masses rotate are 1.2 m and 2.4 m respectively from the left end bearing supporting the shaft. The angle between the arms is 60°. The speed of rotation of the shaft is 200 r.p.m. If the masses are balanced by two counter-masses rotating with the shaft acting at radii of 0.3 m and placed at 0.3 m from each bearing centres, estimate the magnitude of the two balance masses and their orientation with respect to the X-axis, i.e. mass of 10 kg.
The flywheel of a punching machine has a mass of 300 kg and a radius of gyration of 600 mm. Each punching operation requires 2500 J of work. (a ) Knowing that the speed of the flywheel is 300 rpm just before a punching, determine the speed immediately after the punching. (b) If a constant 25-N.m couple is applied to the shaft of the flywheel, determine the number of revolutions executed before the speed is again 300 rpm.
The 8-in. radius brake drum is attached to a larger flywheel that is not shown. The total mass moment of inertia of the drum and the flywheel is 15 lb.ft.s2 and the coefficient of kinetic friction between the drum and the brake shoe is 0.40. Knowing that the angular velocity of the flywheel is 450 rpm clockwise when a force P of magnitude 65 lbf. is applied to the pedal C, determine the number of the revolutions executed by the flywheel before it comes to rest. (The final answer should be in two decimal places with correct units)
A uniform 144-lb cube is attached to a uniform 136-lb circular shaft as shown, and a couple M with a constant magnitude is applied to the shaft when the system is at rest. Knowing that r = 4 in., L= 12 in., and the angular velocity of the system is 960 rpm after 4 s, determine the magnitude of the couple M.
3. The 10-in.-radius brake drum is attached to A a larger flywheel which is not shown. The total mass moment of inertia of the flywheel and drum is 16 lb · ft · s² and the coefficient of kinetic 6 in. friction between the drum and the brake shoe is В 0.40. Knowing that the initial angular velocity is 240 rpm clockwise, determine the force which must be exerted by the hydraulic cylinder if the system is to stop in 75 revolutions. 12 in. D Use work-energy equation. 10 in. +6 in.-
Two 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.
Please display all work
The 7-kg uniform slender bar BD is attached to bar AB and a wheel of negligible mass which rolls on a circular surface. Knowing that at the instant shown bar AB has an angular velocity of 6 rad/s and no angular acceleration, determine the reaction at Point D. B 0.75 m A 1,5 m 0.75 m The reaction at Point Dis 38.315 NA 60
A semicircular panel with a radius r is attached with hinges to a circular plate with a radius r and initially is held in the vertical position as shown. The plate and the panel are made of the same material and have the same thickness. Knowing that the entire assembly is rotating freely with an initial angular velocity of w0 , determine the angular velocity of the assembly after the panel has been released and comes to rest against the plate.