elastically

Elastically is an adverb describing an action performed in an elastic manner or related to elasticity. In physics and engineering, it commonly denotes reversible deformation: a body that is elastically deformed returns to its original shape and size when the external force is removed.

Under small strains, many materials behave elastically, with deformation proportional to the applied load. This linear elastic behavior is described by Hooke's law, often written as sigma = E epsilon, where E is Young's modulus. The work done to deform the material is stored as elastic potential energy and is released when the load is removed.

Elastic collisions, in kinetic theory, are events in which total momentum and total kinetic energy are conserved. In such collisions, no permanent deformation occurs and no energy is transformed into internal energy; the system's kinetic energy remains unchanged in the center-of-mass frame.

In practice, materials have an elastic limit, beyond which deformation becomes plastic and permanent. Real-world materials show deviations from perfect elasticity, including hysteresis and damping, especially at higher strains or varying loading rates. Rubber, springs, and many polymers exhibit high elasticity, while metals typically behave elastically only up to their yield point.

Elastically is used across disciplines such as mechanics, acoustics, and materials science to describe reversible or recoverable responses to stress or deformation. It should not be confused with the broader concept of elasticity, which refers to a material's property of returning to its original shape after deformation.