Physics
posted by Jen .
A 1220 kg car rounds a circular turn of radius 19.2 m. If the road is flat and the coefficient of static friction between the tires and the road is 0.66, how fast can the car go without skidding?

Let mu_s be the static friction coefficient.
If the road is not banked and the car is on the verge of slipping, the maximum static friction force equals the centripetal force.
M*g*mu_s = M*V^2/R
Cancel the M's.
V^2 = R*g*0.66
Solve for V 
5.6

isn't it 11.14? How the heck did you end up with 5.6?
V = sqrt(19.2 * 9.8 * 0.66)
V = 11.14 
11.14, that is