# Centripetal force problem

1. Jun 8, 2014

### BrainMan

1. The problem statement, all variables and given/known data
A car of mass 2000 kg rounds a circular turn of radius 20 m. If the road is flat and the coefficient of friction is 0.7 between the tires and road, how fast can the car go without skidding?

2. Relevant equations
Fc = m(v2/r)

3. The attempt at a solution
I tried to find the centripetal force by doing
2000(9.8) = 19600
19600(.7) = 13720
then I plugged that into the above equation to find the velocity
13720 = 2000v2/202
5488000/2000 = v2
2744 = v2
$\sqrt{}2744$ = v
v= 52.38 m/s. The correct answer is 11.7 m/s

2. Jun 8, 2014

### Nathanael

Why did you square the radius?

Edit:
Other than that you are correct.

3. Jun 8, 2014

### BrainMan

That was my mistake. Thanks!