The problem is problem 6 at http://viewmorepics.myspace.com/index.cfm?fuseaction=viewImage&friendID=128765607&imageID=1460003525 A long thin rod of mass M and length L with two balls of mass M1 (same mass for both) attached is allowed to rotate about the horizontal axis shown. The bar is initially stationary. It is then hig with a piece of putty of mass M2 and speed v which sticks to one of the M1's. a) Find the angular velocity of the system after the collision. The correct answer should be 6M2*v/ (6M1L + 3M2L + ML) b) What angle will the sytem rotate through before coming to a stop? Assume that it must be between 180 and 270 degrees. For part a, Am I suppose to use the conservation of angular momentum. IW = I_f*W_f (1/12)ML^2 *w= (1/12)(M1+M2)*L^2*W_f I am stuck though since I don't know how to account for v. For part b, The answer is 180 + arcsin(V^2/gL) I don't know how to get to v^2/gL.