Equilibrium is the state of a system that is not changing its speed or direction. At rest it is called static equilibrium and during movement it is called dynamic equilibrium. Equilibrium is often used interchangeably with balance but balance is the process of controlling movement during short or long periods rather than the the unchanging state itself, which is equilibrium.
Equilibrium describes a state in which two or more opposing forces, acting against one another balance one another out so that the sum of all the forces acting on the object equal to zero. This is termed translational or linear equilibrium. Also, if an off-axis force or torque that would tend to cause rotation is acting on object, but the net of the moments acting on the system equal to zero, this is called rotational equililibrium.
A state of equilibrium is in accordance to Newton's first law, which states that a body which is at rest or moving, will tend to remain at rest or in motion unless acted on by an external force to bring about a change in the existing state. Whether the human body is at rest or moving, multiple forces act on it at all times. These forces are external, such as the force of gravity, and internal, such as the innate material forces produced by the structure of the body.
This page created 05 Oct 2011 01:58
Last updated 02 Mar 2016 18:06