Disk A, of mass 2 kg and radius r = 60 mm, is at rest when

Disk A, of mass 2 kg and radius r = 60 mm, is at rest when it is placed in contact with a belt which moves at a constant speed v = 15 m/s. Knowing that μk = 0.20 between the disk and the belt, determine the time required for the disk to reach a constant angular velocity.

Disk A, of mass 2 kg and radius r = 60 mm, is at rest when