I got this tricky question, need help.
A uniform rod of mass $M$ and length $L$ is attached to an axis at its top, a bullet with mass $m$ traveling at speed $U$ (horizontal) hits the rod at $2L/3$ from the axis and then LEAVES the rod at speed $U/2$.
I need to find the angular speed of the rod right after collision assuming collision time is very short.
If the bullet stayed in I would just do conservation of angular momentum, find the new moment of inertia with the bullet using Steiner's law and solve for $\Omega$.
But what do I do when the bullet leaves the rod?