1. The problem statement, all variables and given/known data A man of mass M stands on a railroad car which is rounding an unbanked turn of radius R at speed v. His center of mass is height L above the car, and his feet are distance d apart. The man is facing the direction of motion . How much weight is on each of his feet? 2. Relevant equations Sum of forces in the radial direction: -f1-f2 = m v^2 / R Sum of forces n the vertical direction: -W+ N1 + N2 = 0 Sum of torques = 0 3. The attempt at a solution f1 and f2 are the reaction forces on each foot of the man in the radial direction, N1 and N2 are the reaction forces on each of the man's feet in the vertical (up) direction and are balanced by the weight of the man. I need to get an extra equation from the sum of torques around some axis of rotation, but I don't understand which axis it is. The man is not spinning in any direction, but I0m trying to get an equation for the torques caused by N1 and N2 at some distance from a point through the axis of (no-)rotation. Can I calculate the torques around the tangent to the trajectory of motion that goes trough the center of mass, even though the center of mass is being accelerated and therefore isn't an inertial frame of reference? Should I go an try to sum the torques using the center of the curve as the origin of the coordinates, since that is stationary?