I have a little conceptual question about a rod-pivot system. We have this rod (mass M, length l) pivoting about a fixed point. It is released at 30 degrees above the horizontal, and we're asked for the magnitude and direction force on the pivot when the rod reaches the horizontal. So i figured one of the forces on the pivot would be the centripital force keeping the rod in a circular motion. This I can "easily" calculate, and it's always pointing in the -r direction (opposite to the rod). But I can't figure out what and if there are other forces. In fact, I "believe" there are no others. But the question is asked in such a way as to hint there might be something else. If you have any insights, please share tehm with me.