A dad pushes tangentially on a small hand-driven merry-go-round and is able to accelerate it from rest to a frequency of 14 rpm in 12.0 s . Assume the merry-go-round is a uniform disk of radius 2.5 mm and has a mass of 560 kg, and two children (each with a mass of 25 kg) sit opposite each other on the edge. Calculate the torque required to produce the acceleration, neglecting frictional torque. What force is required at the edge?

36. A uniform disk has a mass of 3.7 kg and a radius of 0.38 m. The disk is mounted on frictionless bearings and is used as a turntable. The turntable is initially rotating at 20 rpm. A thin-walled hollow cylinder has the same mass and radius as the disk. It is released from rest, just above the turntable, and on the same vertical axis. The hollow cylinder quickly aquires the same final angular velocity as the turntable. The final angular momentum of the system is closest to: (Hint: Conservation of Angular Momentum) 0.68 kg m²/s 0.56 kg m²/s C. 0.80 kg m²/s d. 0.96 kg m²/s e. 1.1 kg m²/s 37. What can you say about the pressures at points 1 and 2? a. b. a. b. c. a. b. C. C. d. the Ame. C. d. e. a. 53 N b. 61 N 70 N 78 N 87 N P₁> P₂ P₁ P2 P₁< P₂ 38. A 7.1 kg solid sphere, made of metal whose density is 4100 kg/m³, is suspended by a cord. The density of water is 1000 kg/m³. When the sphere is immersed in water, the tension in the cord is closest to: (Hint: F=ma) bbu2 agnh69d casinotiant…

A playground carousel is rotating counterclockwise about its center on frictionless bearings. A person standing still on the ground grabs onto one of the bars on the carousel very close to its outer edge and climbs aboard. Thus, this person begins with an angular speed of zero and ends up with a nonzero angular speed, which means that he underwent a counterclockwise angular acceleration. The carousel has a radius of 1.69 m, an initial angular speed of 3.27 rad/s, and a moment of inertia of 126 kg-m². The mass of the person is 44.1 kg. Find the final angular speed of the carousel after the person climbs aboard.

(a) Calculate the linear acceleration of a car, the 0.310-m radius tires of which have an angular acceleration of 11.0 rad/s². Assume no slippage and give your answer in m/s². m/s² (b) How many revolutions do the tires make in 2.50 s if they start from rest? rev (c) What is their final angular velocity in rad/s? rad/s (d) What is the final velocity of the car in m/s? m/s

A merry-go-round rotates at the rate of 0.25 rev/s with an 75-kg man standing at a point 2.0 m from the axis of rotation. (a) What is the new angular speed when the man walks to a point 1.0 m from the center? Assume that the merry- go-round is a solid 25-kg cylinder of radius 2.0 m. rad/sec (b) Calculate the change in kinetic energy due to this movement. How do you account for this change in kinetic energy? O Wind resistance varies as the square of the speed. O Work is done by the merry-go-round on the man as he moves towards the center. O The moment arm of the man about the axis of rotation decreases. O Work is done by the man on the system as he moves towards the center.

Determine the magnitude of the angular acceleration and applied torque if a uniform disk has the following characteristics: m=12kg, diameter=0.25m and accelerates from rest of 5.30 rad/s in 6 seconds.

A playground merry–go–round has a mass of 132 kg and a radius of 1.60 m and it is rotating with an angular velocity of 0.500 rev/s. What is its angular velocity after a 19.0–kg child gets onto it by grabbing its outer edge? The child is initially at rest.

A car tire (hoop) has a mass of 35 kg and a radius of 0.43 m. The tire is released from rest at the top of a hill and it rolls without slipping to the bottom. “Rolls without slipping” means that the linear velocity of the center of mass is equal to the tangential velocity at the edge of the tire. Once the tire reaches the bottom of the hill it will have dropped by 10 m in vertical height. The final angular velocity ?ω of the tire at the bottom of the hill is Answer ????rads.

A 270-g mass hangs from a string that is wrapped around a pulley, as shown in the figure. The pulley is suspended in such a way that it can rotate freely. When the mass is released, it accelerates toward the floor as the string unwinds. Model the pulley as a uniform solid cylinder of mass 1.00 kg and radius 5.00 cm. Assume that the thread has negligible mass and does not slip or stretch as it unwinds. Determine the magnitude a of the pulley's angular acceleration. 344 rad/s? Incorrect Determine the magnitude of the acceleration a of the descending weight. a = m/s? Question Source: Freedman College Physics 3e | Publ

A dragster starts from rest and accelerates down a track. Each tire has a radius of 0.320 m and rolls without slipping. At a distance of 418 m, the angular speed of the wheels is 255 rad/s. Determine (a) the linear speed of the dragster and (b) the magnitude of the angular acceleration of its wheels. (a) v = (b) a= i i