Speed & Velocity & Friction Force ?

[Nesstle]

Speed & Velocity & Friction Force ?

Homework Statement

With What Max.Speed? a Car can move in horizontal curve with radius r=25m,
if the coefficient of friction is u=0,8

Homework Equations

ƒ = μN S= D/T

The Attempt at a Solution

i tryed bunch of garbages so as i don't kno which is right:S

 

[rock.freak667]

The frictional force provides the centripetal force.

So Frictional force=centripetal force.