11.1.13: Statics

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Statics is primarily the study of bodies in static equilibrium. There are two conditions necessary for static equilibrium: the net force on a body equals zero and the net torque on a body equals zero. This is why we have waited until after discussing rotations to consider statics. Although any body with a constant velocity (of its center of mass) and a constant angular momentum is in equilibrium, the conditions of static equilibrium are most often applied to bodies that are at rest and not rotating. In many disciplines, especially mechanical engineering, understanding principles of statics is essential. After all, we hope that our buildings, bridges, cranes, etc., always maintain static equilibrium.