Equilibrium

How it is used

Used in statics: an object is in equilibrium, reaches equilibrium or is held in equilibrium. Types include static, dynamic, stable and unstable equilibrium. In thermodynamics, thermal equilibrium means two objects have reached the same temperature.

Example sentences

1. The sign hangs in equilibrium, so the tensions in the two cables must balance its weight.

2. A marble at the bottom of a bowl is in stable equilibrium.

Common collocations

• in equilibrium
• stable equilibrium
• unstable equilibrium
• thermal equilibrium
• equilibrium position

Related terms

• net forceThe single force that has the same effect as all the forces acting on an object together. It is the vector sum of those forces and decides the object's acceleration.
• torqueThe turning effect of a force about a pivot or axis. It equals the force multiplied by the perpendicular distance from the pivot and is measured in newton metres (N·m).
• free-body diagramA simple sketch of one object with labelled arrows for all the forces acting on it, each drawn in its own direction. It is the usual first step in solving a forces problem.
• forceA push or a pull that can change how an object moves or change its shape. It has both size and direction and is measured in newtons (N).
• simple harmonic motionA repeating back-and-forth motion in which the acceleration is proportional to the displacement from the centre and always points back towards it. A mass on a spring moves this way.

This word in other fields

The same English word can have a different meaning in another field:

• equilibrium · Economics

More terms: Motion and Forces

• mass
• velocity
• acceleration
• Newton's laws of motion
• gravity
• weight
• friction
• speed
• displacement
• projectile motion
• inertia
• centripetal force