Review Conceptual Example 7 before starting this problem. A uniform plank of length 5.0 m and weight 225 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 409 N walk on the overhanging part of the plank before it just begins to tip?
Physics - drwls, Wednesday, March 2, 2011 at 8:37pm
Where is the left support? We can't see your figure.
This is a static-equilibrium moment balance problem. When there is a zero moment about the right-most suport with zero force on the left-hand support, the plank will begin to tip. Remember to include the monent due to the weight of the plank.