In a downtown office building, you notice each of the four sections of a rotating door has a mass of 80 kg. What is the width, in meters, of each section of the door if a force of 66 N applied to the outer edge of a section produces an angular acceleration of 0.500 rad/s²?

A turntable must spin at 33.3 rev/min (3.49 rad/s) to play an old-fashioned vinyl record. How much torque must the motor deliver if the turntable is to reach its final angular speed in 1.50 revolutions, starting from rest? The turntable is a uniform disk of diameter 30.5 cm and mass 0.230 kg.

A child (mass 20 kg) is at the edge of a spinning merry-go-round (approximated as a solid disk of mass 100 kg, radius 2 m). The child walks towards the center of the merry-go-round until he is halfway from the edge. What is the final angular speed of the merry-go-round if the initial angular speed is 10 rad/s?

A small grinding wheel has a moment of inertia of 4.0 x 10-5 kg ⋅ m2. What net torque must be applied to the wheel for its angular acceleration to be 150 rad/s2?

A torque of 12 N⋅m is applied to a solid, uniform disk of radius 0.50 m. If the disk accelerates at 7 rad/s2, what is the mass of the disk?

A circular disk with a radius of 0.37 m is subject to 2 tangentially applied forces. The disc is fixed such that it will rotate about its center. Both forces produce a torque in the same direction. F1 = 4.7 N applied at the outer edge of the disc. F2 = 3.2 N applied at a distance of 0.3 from the center of the disc. What is the net torque on the disc?

A circular disk with a radius of 0.42 m is subject to 2 tangentially applied forces. The disc is fixed such that it will rotate about its center. Both forces produce a torque in the same direction. F1 = 4.4 N applied at the outer edge of the disc. F2 = 3 N applied at a distance of 0.2 from the center of the disc. What is the net torque on the disc?

A merry-go-round accelerates from rest to 0.74 rad/s in 33 s. Assuming the merry-go-round is a uniform disk of radius 6.0 m and mass 3.10×104 kg, calculate the net torque required to accelerate it. Express your answer to two significant figures and include the appropriate units.

A car is traveling at a constant speed on the highway. It’s tires have a diameter of 66.0 cm and are rolling without sliding and slipping. If the angular speed of the tires is 50.0 rad/s, what is the speed of the car?

An object has a moment of inertia of 0.79 kg m2. Its angular velocity is increasing at the rate of 0.40 rad/s per second. What is the net torque (in N m2) on the object?