1. The problem statement, all variables and given/known data A car enters a turn whose radius is ##R##. The road is banked at angle ##\theta##, and the coefficient of friction between the wheels and the road is ##\mu_s##. Find the minimum and maximum speeds of the car to stay on the road without skidding sideways 2. Relevant equations Polar coordinates Newton's laws 3. The attempt at a solution So I am confused about how to get started on this problem. I know that there are three forces acting on the car (friction, gravity, and normal force). But I am confused about how to put this into equations that involve the radius and the centripetal force. I have tried using polar coordinates, but since the vehicle is on a banked turn, the forces don't really align in any way. How should I get started? (Once I have the equations it seems that the problem is not too hard).