🔋college physics i – introduction review

Unstable equilibrium

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Unstable equilibrium occurs when an object, if slightly displaced, tends to move further away from its original position. This type of equilibrium is sensitive to perturbations and does not return to its initial state.

5 Must Know Facts For Your Next Test

  1. An object in unstable equilibrium has a high center of mass relative to its base of support.
  2. Small disturbances cause the object to move further from its equilibrium position.
  3. Examples include a pencil balanced on its point or a ball on top of a hill.
  4. In terms of potential energy, unstable equilibrium corresponds to a local maximum.
  5. Mathematically, the second derivative of the potential energy with respect to position is negative at unstable equilibrium points.

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