1. The problem statement, all variables and given/known data A curve with a 135 m radius on a level road is banked at the correct angle for a speed of 20m/s. If an automobile rounds this curve at 30m/s, what is the minimum coefficient of static friction between tires and road needed to prevent skidding? 2. Relevant equations N=mg(cos\theta) mgsin(\theta)=centripetal force=mv^2/r Quite confused with the workings for this question, anyone can help?