1. The problem statement, all variables and given/known data what is the maximum speed with which a 1500kg car can make a left turn around a curve of radius 50m on a level road without sliding? 2. Relevant equations 3. The attempt at a solution i already got the answer....but my question is: f_s points left and the equation sigmaF_r = f_s = mv^2/r why isn't it negative if the force in the free body is pointing left? is it because the car is turning left?