What is the Net Force on a Block Against a Wall With Static Friction?

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
3 replies · 3K views
kathmill
Messages
4
Reaction score
0

Homework Statement


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).


Homework Equations



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

The Attempt at a Solution



F = Fs + Fn

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

Thanks!
 
Physics news on Phys.org
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...
 
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 each other?
 
Yeah you got the direction of the forces...
So what you have in essence is
http://geocities.com/hackers_007_008/Untitled.jpg