(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A curve of radius 68m is banked for a design speed of 85km/h. If the coefficient of static friction is 0.30 (wet pavement), at what range of speeds can a car safely make the curve?

2. Relevant equations

1) F_{N}sin(theta) = m*v^{2}/r

2) F_{N}cos(theta) - mg = 0

3) tan(theta) = v^{2}/rg

3. The attempt at a solution

I used the third equation to find (theta) which is 39.9^{o}

but I can't find out how to find F_{fr}or the range of velocity

I understand that when the car goes slow the frictional force faces up the banked curve and when it goes fast the friction goes down the banked curve but I can't figure out how to solve the question.

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# Homework Help: Banked Curve Question

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