# Static friction question.

1. Oct 19, 2004

### Bailey

A 10KG block is resting on a plane inclined at an angle of 30 degrees from the horizontal. Find the force of frction holding the block stationary. is it possibel to calculate the exact coefficient of static friction from the above information? explain.

for this quesiton, I can find the force of friction. BUT, since:

static friction = coefficient of static friction * normal force

from the above equation we can solve for the exact coefficient right? since we know the normal force & the friction force.

now i know static frition will vary depending on the force acting on the object, but since the block is stationary, and the force of gravity acting on it is constant, which mean the coefficient of static will not change.

why can't we find the the coefficient of static friction?

edit- ops......i just noticed...........i shoulda posted in the classcial physic group................err...............can some mod help me move this topic there?

Last edited: Oct 19, 2004
2. Oct 19, 2004

### arildno

Because the coefficient is the coefficient of MAXIMAL static friction,not the coefficent of static friction per se.

3. Oct 19, 2004

### Bailey

ahhh......................thx.