Statics is the branch of mechanics concerned with the analysis of loads (force , torque/moment ) on physical systems in static equilibrium , that is, in a state where the relative positions of subsystems do not vary over time, or where components and structures are at a constant velocity. When in static equilibrium, the system is either at rest, or its center of mass moves at constant velocity. The study of moving bodies is known as dynamics , and in fact the entire field of statics is a special case of dynamics.^[1]