The 2-kg collar C is free to slide along the smooth shaft AB. Determine the acceleration...

The 2-kg collar C is free to slide along the smooth shaft AB. Determine the acceleration of collar C if (a) the shaft is fixed from moving, (b) collar A, which is fixed to shaft AB, moves to the left at constant velocity along the horizontal guide, and (c) collar A is subjected to an acceleration of 2 m/s² to the left. In all cases, the motion occurs in the vertical plane.