Hey lads, i solved part a of this problem in 5 minutes, part B is killing me, ive been doing it for 1 hour and nothing.. ive tried everything, any help appreciated: [Tipler5 5.P.090.] A civil engineer is asked to design a curved section of roadway that meets the following conditions: With ice on the road, when the coefficient of static friction between the road and rubber is 0.05, a car at rest must not slide into the ditch and a car traveling less than 50 km/h must not skid to the outside of the curve. What is the minimum radius of curvature of the curve and at what angle should the road be banked? ____??? m 2.862° (i found this and its correct) i really dont know if im thinking right anymore after 1 hour of this + other stress that came on so well here is the last thing i tried.... i set my set of axis parallel to the banked road, so the positive Y is the normal force.... and the friction force goes parallel the banked road.... i set the force friction going up the hill to balance the weight component going down the banked road and i had a force component (mv^2/r)/(cos(2.862) Well i dont even know what im doing anymore.. i know at first i must of been close to solving it but now im too tired to reason ... help appreciated, thanks!