Static equlibrium with friction

[canicon25]

Homework Statement

a 4.0kg block is held against a brick wall and is just kept from sliding down by the force F. The coefficient of friction is 0.35 between the block an d the wall.

Find the normal force and the minimum force F that will keep the block from sliding.

Homework Equations

Sum Fx = 0
Sum Fy = 0

The Attempt at a Solution

Fx=Fnormal
Fy+Ffriction=mg

uFx=Ffriction

Fy+uFx=39.2

 

[ehild]

Hi canicon,
Your equations are correct, but one is missing.
It is given that the force encloses a 30° angle with the vertical. That means a relation between Fy and Fx. What is it? Adding this relation to the other equations, you can get Fx and Fy.
ehild