# Homework Help: Determining distance of travel with friction acting on a car.

1. Nov 12, 2009

### quinntan

1. A car is traveling at 51 mi/h on a horizontal highway. If the coefficient of static friction between the road and tires on a rainy day is .102 what is the minimum distance in which the car will stop.

2. f=un f=ma kinetics equations

3. No idea here. Teacher barely skimmed over friction so far and all problems we have done in class either had a value of acceleration, a mass or a force. This one has none of those.

2. Nov 12, 2009

### indr0008

can u imagine what will happen to the car?

3. Nov 12, 2009

### quinntan

I know it will stop eventually but I don't know how far it will go. I made a free body diagram but it wasn't very useful without knowing the cars mass.

4. Nov 14, 2009

### indr0008

In your free body diagram, do u have these 3 forces:

the weight od the car, the normal force exerted by the ground, and the friction force? :)

5. Nov 14, 2009

### quinntan

Alright I got it. It turns out that the masses cancel.