# Stopping Distance

1. Oct 7, 2006

### Soaring Crane

Three cars (cars F, G, and H) are moving with the same velocity, and slam on the brakes. The most massive car is F, and the least massive is H. Assuming all 3 cars have identical tires, which car travels the longest distance to skid to a stop?

Will they all travel the same distance in stopping?
If mgh = mv^2/2 for each car:

F – (3mv^2)/2 = 3*mgh h = v^2/2g
G – (2mv^2)/2 = 2mgh h = v^2/2g
H – mv^2 = mgh h = v^2/2g

Thanks.

2. Oct 7, 2006

### Astronuc

Staff Emeritus
The same tires implies the same coefficient of friction, u or $\mu$.

The force of friction applies, Ffriction = $\mu$mg, and the energy dissipated is Efriction = Ffriction*d, where d is the distance traveled.

Find dF = dG = dH.

3. Oct 7, 2006

### Soaring Crane

How do I find the energy of friction to find each car's d?

To find d, it would be E/F?

Thanks again.