Hi, I am confused a little bit with the forces acting on a vehicle when it's negotiating a bend, at constant speed. Please click the link to see my sketch. On the plan view I see that it's moving with constant speed, along a circular route. That means there is unbalanced force causing central acceleration. F=mv2/R. Then going to the section I showed the forces acting on the vehicle. Gravity, Normal Force and the friction. These should be the forces causing this F (central acceleration). Equation 1, 2, 3 and 4 are the ones I have but somehow I couldn't get to the 5 which is given as the overall formula for such movements. Can you please tell me what I am doing wrong? Thanks in advance.