Roller Coaster and Apparent Weight

[thebigeis]

Circular Motion

Situation:
A concrete highway curve of radius 70m is banked at a 15 degree angle.

Question:
What is the max speed with which a 1500kg rubber-tired car can take this curve without sliding?

Feedback:
I learned that the static coeffiecient of friction of rubber on concrete is 1.0 for this problem.

I tried net Force = StaticFrictionCoefficient(Normal Force)
Normal = Weight = Mass * Gravity

So I ended up with-
F = 1(1500*9.8) = 14700N
Then I did 14700 * 70cos(15).
Not the right answer... not sure what I'm doing, obviously

 

[member 553083]

.Answer:The correct equation to use for this problem is F = mv2/R, where m = mass of the car, v = velocity and R = radius of the highway curve. Plugging in the given values, we get: F = 1500 * v2 / 70 Solving for v, we get: v = sqrt(14700 * 70) = 140.4 m/s Therefore, the max speed with which a 1500kg rubber-tired car can take the highway curve without sliding is 140.4 m/s.