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• Center of gravity


  The point where the total weight of the body is assumed to be concentrated
• Dynamic equilibrium


  A state of equilibrium in which the net external force and torque on a system moving with constant velocity are zero
• Mechanical advantage


  The ratio of output to input forces for any simple machine
• Neutral equilibrium


  A state of equilibrium that is independent of a system's displacements from its original position
• Perpendicular lever arm


  The shortest distance from the pivot point to the line along which the force lies
• SI units of torque


  Newton times meters, usually written as N·m
• Stable equilibrium


  A system, when displaced, experiences a net force or torque in a direction opposite to the direction of the displacement
• Static equilibrium


  A state of equilibrium in which the net external force and torque acting on a system is zero
• Torque


  Turning or twisting effectiveness of a force
• Unstable equilibrium


  A system, when displaced, experiences a net force or torque in the same direction as the displacement from equilibrium