# Angular momentum conservation: determine velocity of impactor

1. Oct 16, 2016

### Vitani11

• Thread title changed to reflect problem description
1. The problem statement, all variables and given/known data
A uniform rod of length L and mass M hangs at rest from a frictionless pivot. The rod is hit a distance 0.8L below the pivot by a particle of mass m moving perpendicularly to the rod at speed v; the particle sticks to the rod. Following the collision, the maximum angle between the rod and the vertical is 90 deg. What is v?

2. Relevant equations
See attached

3. The attempt at a solution
See attached

2. Oct 16, 2016

### Vitani11

This is where I'm at. I need another equation for t in terms of moment of inertia, mass, or radius. At least I am about 80% sure that is all I need left to solve this.

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3. Oct 16, 2016

### Vitani11

In case you're wondering where ωf came from: It is the arclength equation S=rθ divided by time, where theta was given as π/2 (90 deg) and r is L.