Ap physics friction force please help!!!! 1. The problem statement, all variables and given/known data A 1000kg car traveling at a speed of 40m/s skids to a halt on wet concrete where the friction force is 6000N. How far does the car slide before coming to a stop? 2. Relevant equations F=mv^2 / r 1000 kg x (40 m/s^2) / r = 6000 N I got 266.7 3. The attempt at a solution I came up with a positive number and it should be a negative number... What am I doing wrong?!