# Friction problem

1. Aug 8, 2006

### ksle82

A car travelling at an initial velocity $$v_{0}$$ applies its brakes to come to a stop. The coeffictien of friction is $$\mu$$. What distance is required to stop?

I know that you can solve for x using this equation:
$$v^2=v_{0}^2+2ax$$

-but i don't know how to solve for acceleration a. any help?

Last edited: Aug 9, 2006
2. Aug 8, 2006

### Office_Shredder

Staff Emeritus
Can you calculate the frictional force? If so, can you calculate the acceleration, by, say, using the definition of force? Try it out, assigning the mass to be m0, and see what you get

3. Aug 9, 2006

### ksle82

Im trying to do a force balace to find a but im not sure this is right.

$$-\mum_{0}g=m_{0}a$$
solving for for a, i get $$a=\mug$$

Last edited: Aug 9, 2006
4. Aug 9, 2006

### ksle82

excuse my bad Latex

but it should be:

-u*Mo*g=Mo*a, solving for a,

a=-u*g

5. Aug 9, 2006

### daniel_i_l

yes thats right!

6. Aug 9, 2006

### ksle82

thanx 'preciate the help