Conservation of angular momentum when a system changes configuration.

A uniform cylinder, mass M= 12 kg, radius R= .36 m, is initially rotating about a vertical axis through its center at angular velocity wo= 6.6 rad/sec. Now two small (point masses), each of mass m= 2 kg, are dropped onto and stick to the cylinder, each at distance r= .24 m from the axis. SEE ATTACHMENT for diagram.
Find wf, the final angular velocity of the combined three objects after the drop.

Solution:
<br>Note 1.
<br>If no external torque is applied to a system, its total angular momentum remains constant.
<br>Note 2.
<br>Recall that the angular momentum, L, of a rotating object with moment of inertia I, and angular rotation speed w is:
<br>(1) L= I ...

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