Editing Young's modulus (section)

===Linear elasticity===
{{Main|Linear elasticity}}
A solid material undergoes [[elastic deformation]] when a small load is applied to it in compression or extension. Elastic deformation is reversible, meaning that the material returns to its original shape after the load is removed.

At near-zero stress and strain, the stress–strain curve is [[linear]], and the relationship between stress and strain is described by [[Hooke's law]] that states stress is proportional to strain. The coefficient of proportionality is Young's modulus. The higher the modulus, the more stress is needed to create the same amount of strain; an idealized [[rigid body]] would have an infinite Young's modulus. Conversely, a very soft material (such as a fluid) would deform without force, and would have zero Young's modulus.