A solid disk of mass m1 = 9.1 kg and radius R = 0.25 m is rotating with a constant angular velocity of ω = 34 rad/s. A thin rectangular rod with mass m2 = 3.5 kg and length L = 2R = 0.5 m begins at rest above the disk and is dropped on the disk where it begins to spin with the disk.
1. What is the initial angular momentum of the rod and disk system? (9.66)
2. ) What is the initial rotational energy of the rod and disk system? (164.3)
3) What is the final angular velocity of the disk? I need help with this

Question

A solid disk of mass m1 = 9.1 kg and radius R = 0.25 m is rotating with a constant angular velocity of ω = 34 rad/s. A thin rectangular rod with mass m2 = 3.5 kg and length L = 2R = 0.5 m begins at rest above the disk and is dropped on the disk where it begins to spin with the disk.
1. What is the initial angular momentum of the rod and disk system?  (9.66)
2. ) What is the initial rotational energy of the rod and disk system? (164.3)
3) What is the final angular velocity of the disk?  I need help with this

anonymous · Answer

1)
angular momentum is equal to angular velocity X mass