Homework Help: Horizontal and Friction Forces

1. Dec 16, 2008

kathmill

1. The problem statement, all variables and given/known data
A horizontal force F pushes a block of weight 5.0 N aganist a vertical wall. The coefficient of static friction between the wall and the block is 0.25. The force F is the minimum required to hold the block in place.
Find the magnitude of the net force on the block by the wall (include both normal force and friction force).

2. Relevant equations

F = ma
Fs = coefficient of static friction * normal force.

3. The attempt at a solution

F = Fs + Fn

I don't understand how to calculate the horizontal aspect of it? Any help?

Thanks!

2. Dec 16, 2008

avenkat0

Draw a free body diagram for the mass, the upward/downward forces and the left/right forces...
what keeps the mass from sliding up and down and what keeps the mass from going through the wall...

3. Dec 16, 2008

kathmill

So the static friction force is an upward force and mg is a downward force; whereas the force applied (which I am trying to find) and the normal force are left/ right forces. But how do the up/down and left/right compare to eachother?

4. Dec 16, 2008

avenkat0

Yeah you got the direction of the forces...
So what you have in essence is
http://geocities.com/hackers_007_008/Untitled.jpg