Consider a 6·kg disk with a radius of 0.6·m and rotating about an axis passing through its center.

Question

(a) What is its rotational inertia? kg·m2

(b) Suppose the disk is rotating counterclockwise and slowing down with a rotational acceleration of 5·rad/s2. What is the net torque acting on the disk? N·m

(c) Suppose the torque you found for the last part is being produced by a force applied at a point 0.3·m from the axis. If the direction of the force is perpendicular to a line from the axis to that point, what is the magnitude of the force? N

Answer 1

Rotational inertia I=mr^2 while m is 6 kg and r is 0.6 m

B) torque =Ia while a is -5 rad/s