posted by Maa .
A force of 100 N is applied tangentially to a disk of radius 10 cm and mass 0.5 kg. the disk is initially at rest. What is the angular acceleration of the disk? How many revolutions does the disk goes through after 10 sec. How much rotational work was done on the disk?
Angular acceleration = Torque/(moment of inertia)
The moment of inertia is (1/2) M R^2 for a disk.
After 10 seconds, the number of radians turned is
theta = (1/2)(angular acceleration)*(10 s)^2
Divide that by 2 pi for the number of revolutions.
Rotational work done is (torque)*(theta)