Forces, Torque, and Structural Balance

Equilibrium in mechanics is a special case where an object or system has both zero net force and zero net torque. When that happens, linear acceleration and angular acceleration are also zero. The object may stay at rest, or its center of mass may move at a constant velocity.

Even in equilibrium,...

Equilibrium is a special case in classical mechanics but is ubiquitous in everyday life, while free-body diagrams help decipher the underlying forces present.

A system is in translational equilibrium if the forces acting on it are balanced, that is, the net force is zero. Equilibrium can also be established in a rotational system if the n...