Since stress is proportional to load and strain is proportional to deformation, this implies that stress is proportional to strain. Hooke's Law is the statement of that proportionality. The constant, E , is the modulus of elasticity, Young's modulus or the tensile modulus and is the material's stiffness. If a material obeys Hooke's Law it is elastic. The modulus is insensitive to the material's temper.
Normal force is directly dependent upon the elastic modulus.
The maximum stress a material withstands when subjected to an applied load. Dividing the load at failure by the original cross sectional area determines the value. The ratio of stress to corresponding strain at any point on the stress-strain curve beyond the proportional limit is the secant modulus. Yield strength Constructing a parallel line to OA at a specified offset strain establishes the yield strength. F is the yield strength at G offset.