1. The problem statement, all variables and given/known data A uniform plank of length l = 6m and mass M= 90kg rests on sawhorses separated by D = 1.5m and equidistant from the center of the plank. Cousin Throckmorton wants to stand on the right-hand end of the plank. If the plank is to remain at rest, how massive can Throckmorton be? Diagram: 2. Relevant equations 3. The attempt at a solution I am confused at the diagram. Why is the centre of gravity not at the centre of mass of the plank which should be in the middle ?