1. The problem statement, all variables and given/known data http://online.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/oldexams/exam3/sp08/fig15.gif [Broken] The force exerted on the plank by the wall is upwards. (True/False) 2. Relevant equations 3. The attempt at a solution In statics, when using [tex]\sumFy = 0[/tex], i thought the forces exerting on the wall should cancel the force of gravity (weight : mg).. That's the reason why i thought the statement to be TRUE. But it's actually FALSE........... How to decide the direction of forces? (I am always confused with this..) Please could someone help me out here?