stable equilibrium

physics

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July 14, 2026

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In physics, stable equilibrium describes a state where a system, if slightly disturbed, will return to its original position. This occurs when the net force and net torque acting on an object are zero, and any displacement creates opposing forces that restore it to equilibrium.12

An example of stable equilibrium is a weight suspended by a spring or a brick resting on a flat surface. In contrast, unstable equilibrium is a state where any slight displacement causes the system to move further away from its original position. A fundamental principle related to stable equilibrium is that a system will naturally move towards a state of minimum potential energy.234

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equilibrium
…equilibrium is said to be stable if small, externally induced displacements from that state produce forces that tend to oppose the displacement and return the body or particle to the equilibrium state. Examples include a weight suspended by a spring or a brick lying on a level surface. An equilibrium…
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…equilibrium is said to be stable if small, externally induced displacements from that state produce forces that tend to oppose the displacement and return the body or particle to the equilibrium state. Examples include a weight suspended by a spring or a brick lying on a level surface. An equilibrium…
Read More

particle accelerator
Synchrocyclotrons
…rising, through zero) corresponds to stable equilibrium. If a particle should arrive a short time before the voltage has fallen to zero, it is accelerated. Its speed therefore increases, but the radius of its orbit increases by an even larger proportion, so that the particle will take longer to reach…
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…rising, through zero) corresponds to stable equilibrium. If a particle should arrive a short time before the voltage has fallen to zero, it is accelerated. Its speed therefore increases, but the radius of its orbit increases by an even larger proportion, so that the particle will take longer to reach…
Read More