# I need some help understanding a problem regarding Friction Force.

1. Oct 7, 2011

### patowlmc

1. The problem statement, all variables and given/known data
This problem is regarding Friction Force:

Imagine a skateboard, low and with well-oiled bearings. What would happen if, standing over it at rest, you begin to walk along its length?

3. The attempt at a solution
There are 4 options. I chose this one:
It would start moving in the opposite direction.

The book says it's the correct Answer, but I'm not quite sure why that is.

Is it because the Static friction coefficient is bigger than the force I exert on the skateboard by walking?

P.D. Would it be against the rules if I post a new question, about the same topic in this same thread, once I get the last one answered?

Last edited: Oct 7, 2011
2. Oct 7, 2011

### Raptorkiller

its not that its because action reaction.when you walk forward you exert a backward force on the skateboard which moves you forward and the backward force exerted by you moves the skateboard backward

3. Oct 7, 2011

### patowlmc

Wow! Thanks, It seems a little more logical hehe :P

And it makes sense, since I'm studying Newton's 3 laws of motion. Thanks :)

4. Oct 7, 2011

### Raptorkiller

welcome!!!if possible you can head for my question

Last edited: Oct 7, 2011
5. Oct 7, 2011

### patowlmc

You mean this question: "CHALLENGING pHYSICS questions(dedicated for lover's of physics)" 'Cause if so, I'm totally trying to solve that one, right after my Physics exam on Friday (Today :D )

It seems interesting, mainly because I'll have to read some old stuff, as well as some new stuff to even attempt to solve it.

Bye!! See you around :)