Question

Based on Hooke's law, when is stress proportional to strain?

A) Until the elastic limit
B) Beyond the yield point
C) In the plastic deformation region
D) At the ultimate tensile strength

Answer 1

Stress is proportional to strain in accordance with Hooke's law only until the material reaches the elastic limit.

Step-by-step explanation:

Based on Hooke's law, stress is proportional to strain only until the elastic limit of a material. When a load is applied to a material, an initial linear relationship exists between stress and strain, which follows Hooke's law. However, this proportionality only holds up until the point known as the linearity limit. As the load continues to increase beyond the linearity limit, the relationship between stress and strain becomes nonlinear but still remains in the elastic region. Once stress reaches the elasticity limit, also known as point E, the material starts to undergo plastic deformation, and the stress is no longer proportional to strain.