Term used to describe physical or chemical stasis. Physical equilibrium may be divided into two types: static and dynamic. Static equilibrium occurs when the components of forces and torques acting in one direction are balanced by components of forces and torques acting in the opposite direction. A system in static Click on Term to Read More involving species in more than one phase. Compare Equilibrium involving only one species in a single phase. For example, all gases, all liquids or all solids. Click on Term to Read More.