# A solid disk (M = 10 kg and R - 70 cm ) is rotating at...

###### Question:

A solid disk (M = 10 kg and R - 70 cm ) is rotating at 300 rpm initially. Then a smaller ring (m = 3.0 kg and r 40 cm ) is dropped concentrically onto the disk and they rotate together with a new angular velocity. (Hint: the rotational inertia of the small ring is mr, not ' mr !) 20. find the final angular velocity of the system in rpm. 21. find the change in rotational kinetic energy of the system. CoM 22. find the percent of energy loss during this collision between the solid disk and the ring.