# Homework Help: Are these even possible? (Friction Related)

1. Sep 28, 2008

### bassboy

1. The problem statement, all variables and given/known data
An object rests on an inclined plane. One end of the plane is lifted until the object begins to slide. The angle at which the object begins to slide is 35 degrees. What is the Coefficient of Friction

2. Relevant equations
fk = µkFn
fsmaxsFn

3. The attempt at a solution
Honestly, I don't even know where to begin on this one. Only one variable is given, in what looks (to me) to be a problem where more than one variable is called for to be solved.
Similarly....

1. The problem statement, all variables and given/known data
Nike uses a sole for a line of shoes that has a coefficient of friction, µ=.3. Find the maximum acceleration that a runner using these shoes can have.

2. Sep 29, 2008

### tiny-tim

Welcome to PF!

Hi bassboy! Welcome to PF!

Hint: What is the normal force, Fn, when the angle is 35º?
Show us what you've tried, and where you're stuck, and then we'll know how to help.