# Urgent help on Friction/Forces problem due tomorrow

1. Oct 27, 2009

### Blkmage

Urgent help on static force at the top of an incline DUE TOMORROW

1. The problem statement, all variables and given/known data
A 5.0 kg block on an inclined plane (angle 37 degrees) is acted on by a horizontal force F with magnitude 50 N. The coefficient of kinetic friction between block and plane is 0.30. The coefficient of static friction is not given (but you might know something about it). What happens to the block after it reaches the highest point? Justify your answer.

2. Relevant equations

At the highest point:
F(net, parallel)=0

3. The attempt at a solution

I know that at the highest point, the friction reverses direction and becomes static since the block is at rest momentarily. However, I have no idea how to use this information to answer the question. I drew an FBD but at the top, does the 50 N horizontal force vanish or is it still there?

And could I solve for the static coefficient of friction by setting the sum of forces parallel to the plane equal to 0? How do I go about EXPLAINING what happens?

Last edited: Oct 27, 2009
2. Oct 27, 2009

### Blkmage

Please, I've got a recitation in front of the class tomorrow on this problem. Any help would be greatly appreciated