# Homework Help: Angular momentum of a rod help

1. Oct 16, 2007

### snoggerT

The figure below is of an overhead view of a thin uniform rod of length 0.790 m and mass M rotating horizontally at angular speed 22.0 rad/s about an axis through its center. A particle of mass M/3.00 attached to one end is ejected from the rod and travels along a path that is perpendicular to the rod at the instant of ejection. If the particle's speed vp is 6.00 m/s greater than the speed of the end of the rod just after ejection, what is the value of vp?

Li=Lf, L=Iw, l=rmv

3. The attempt at a solution
- I haven't been able to attempt this problem because I'm having problems setting it up. I'm trying to set up the initial side right now and I am using 1/12ML^2 for the rod, but unsure what to use for the particle since it's inside of the rod. I think I can solve the problem if I can get past this step.

2. Oct 17, 2007

### learningphysics

Use conservation of angular momentum. The angular momentum of the particle about the center is mvr