How large must the coefficient of static friction be between the tires and the road ?

Question

How large must be the coefficient of static friction be between the tires and the road if a car is to round a level curve of radius 130.5 m at a speed of 17.1 m/s?

Answer 1

The car is undergoing uniform circular motion with v = 17.1 m/s and R = 130.5

The centripetal acceleration a_c = v² / R = 2.24 m/sec²

The only force available to cause this acceleration is the force of friction = µ m g, where

µ is the coefficient of friction, m is the mass of the car and g = 9.81

Using Newton's second law: µ m g = m a_c , so µ = a_c / g = 0.228