Hi all, recently joined and having abit of trouble with a problem (several actually but I managed to figure out how to get started on one of them). In any case the problem says: Four thin, uniform rods each of mass M and length d = .75 m, are rigidly connected to a vertical axle to form a turnstile. The turnstile rotates clockwise about the axle, which is attached to a floor, with initial angular velocity w = -2.0 rad/s. A mud ball of mass m = M/4 and inital speed vi = 15 m/s is thrown and sticks to the end of one rod at an angle 60 degrees. Find the final angular velocity of the ball-turnstile system. Now I think I have to use the Conservation of Angular momentum. As such I need to find the inertia of the turnstile which I think turns out to be IT=(4/3)*M*d^2 I think the formula I'm going end up with will probably be It * wf + Ib * wf = IT* wi + angular momentum of the ball before the contact The thing is I don't know how to get further from here.