A solid disk with a mass of 100kg and a radius of 0.2m, turns clockwise through an angular displacement 10 rad when starting from rest to attain its maximum angular speed, of 1 revolution every 0.5s. What is the angular acceleration that the wheel experienced in order to attain maximum speed? How much time did it take for the disk to go from rest to maximum angular speed?

1 answer

1 rev/0.5s = 2 rev/s
-> 12.57 radians/s
= final angular velocity = wf

Time required = 10 rad / (average angular velocity wf/2
= 10/6.28 = 1.59 s

Angular acceleration = wf/t
= 7.9 rad/s^2

The mass and radius of the wheel are not needed to answer the questions, but would be needed for the required torque.