What must be the radius of an unbanked (flat) curve so that a car can safely travel at a maximum speed of 39 m/s? The coefficient of static friction is 0.70.

Answer 1

m v^2/r = .7 m g

or
Ac = .7 g :)

39^2 / r = .7 (9.81)

r = 39^2/ (.7*9.81)