- #1
isukatphysics69
- 453
- 8
A block weighing 22 N is pushed against a vertical wall by a force of magnitude 60 N directed 30° above the horizontal. The block is intitally at rest. The coefficient of static friction between the wall and the block is 0.55 and the coefficient of kinetic friction between them is 0.38.What is the force of friction between the block and the wall? Express your answer as positive if the force of friction points up.
Homework Equations
f=m*a
The Attempt at a Solution
netforcey = 60sin(30)-mg+0.55*normalforce
netforcex = 60cos(30)-normalforce
since the block is not moving in x direction a = 0 so normalforce=60cos(30)
since looking for just friction and block initially at rest normalforce*staticfrictioncoefficient = friction force
since gravity point down friction force point up 0.55*normalfoce = 29 NEWTONSi didn't mean to post pic with -29 NEWTONS i meant 29 NEWTONS but either way still wrong