A 1200 kg car rounds a curve of radius 70m with a banking of 12°. The car is traveling 90 km/h, will a frictional force be required? If so, how much?

Answer 1

v = 90000 m / 3600 s = 25 m/s

centripetal force necessary = 1200 * 25^2 / 70 = 10.7 kN

vertical force = m g = 1200 * 9.81 = 11.8 kN

normal force = m g cos(12º) = 11.5 kN
... horizontal component = 11.5 * sin(12º) = 2390 N

necessary horizontal friction force = 10.7 kN - 2.4 kN = 8.3 kN