1. The problem statement, all variables and given/known data A stationary bicycle wheel is placed on its rim on rough ground. It topples over. Sketch a free body diagram for the wheel when it is at an arbitrary angle to the vertical and label the forces. Explain qualitatively what happens to the direction and magnitude of each of the forces during the toppling process. What I dont get is how the forces change direction and magnitude. 2. Relevant equations 3. The attempt at a solution What i did was draw the forces like in the picture. Not really sure how they change. I'm thinking at first when theta is small Normal ~ mg. Then friction increases and the normal force decreases. Any help greatly appreciated.