Calculate CM Speed of Rod on Compressed Spring

[Sumbhajee]

Homework Statement

A thin uniform rod has mass M = 0.31 kg and length L= 0.45 m. It has a pivot at one end and is at rest on a compressed spring as shown in (A). The rod is released from an angle θ1= 57o, and moves through its horizontal position at (B) and up to (C) where it stops with θ2 = 107o, and then falls back down. Friction at the pivot is negligible. Calculate the speed of the CM at (B).

http://schubert.tmcc.edu/res/msu/physicslib/msuphysicslib/21_Rot3_AngMom_Roll/graphics/prob32a_RodOnSpring.gif

Homework Equations

The Attempt at a Solution

Not sure where to start on this one. Thank you for your time and any help provided.

 

[rl.bhat]

Where is the figure? Problem is not clear without that.