Question

If a curve with a radius of 98 m is properly banked for a car traveling 75 km/h, what must be the coefficient of static friction for a car not to skid when traveling at 99 km/h ?

Answer 1

first we need to find banking angle

x = arctan ( v^2/ rg)

x = arctan ( ( 75* 5/ 18)^2 / 98*9.8)

x = 24.32

as we know expression for fricitonal banked curves

v^2 / rg = ( tan x + u) / ( 1 - u tan x)

(99*5/18)^2 / (98*9.8) = ( tan 24.32 + u) / ( 1 - u tan 24.32)

u = 0.4153

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