Block on a Plane - Friction problem

[bd2015]

Block on a Plane -- Friction problem

edit: deleted

 

[tms]

You don't care in this problem about the interaction of the wedge and the table, since the table is frictionless. You care about the interaction of the wedge and the block, but even there you don't care about kinetic friction.

You have to solve for two different values of the applied force: one that will be just enough to keep the block from sliding down, and one that will be just less than enough to make the block slide up.

Start by drawing a free-body diagram to identify all the forces acting on the small block.