Definition:Equilibrium (Mechanics)/Unstable

This page is about equilibrium in the context of mechanics. For other uses, see equilibrium.

Definition

Let $B$ be a particle, a system of particles, or a body which is in equilibrium.

Let $B$ be such that if a displacement is applied, however small, $B$ moves to a position different from both its original position and its displaced position.

$B$ is then said to be in unstable equilibrium.

Also see

• Definition:Stable Equilibrium
• Definition:Neutral Equilibrium

• Results about unstable equilibrium can be found here.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): equilibrium
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): equilibrium