I don't know if you guys can clearly see the image attached. (sorry i don't have my good digitial camera with me here). But the question is: A 0.5 kg block B slides without friction inside a slot cut in arm OA which rotates in a vertical plane at a constant rate, (dΘ /dt) = 2 rad/s. At the instant when Θ = 30 degrees, r = 0.6 m and the force exerted on the block by the arm is zero. Determine, at this instant, (a) the relative velocity of the block with respect to the arm (b) the relative acceleration of the block with respect to the arm. I believe I am on the right track and I did solve for the velocity of the block in transverse and radial terms. I got: Vradial = (-0.6928) m/s and Vtransverse = (1.2) m/s I have to find the velocity of the arm, and I did (not sure if its right), but my relative velocity is not coming out right... Any help would be greatly appreciated.