System in Equilibrium
A system is in equilibrium when the sum of all forces is zero.
For example, consider a system consisting of an object that is being lowered vertically by a string with tension, T, at a constant velocity. The system has a constant velocity and is therefore in equilibrium because the tension in the string (which is pulling up on the object) is equal to the force of gravity, mg, which is pulling down on the object.
Read more about this topic: Tension (physics)
Famous quotes containing the words system and/or equilibrium:
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