Within the elastic limit of a material, modulus of elasticity is the ratio of:
The ratio of stress o strain in the linear region is called the elastic modulus or elastic constant. The most direct way to measure elasticity is to measure the extension of a portion of a rod under axial tension.
The ratio of applied stress (force/area) 1o axial strain (extension/length) produces the modulus called Young's modulus.
E = σ/e
E is the Young’s Modulus of the material given in N/m2 σ is the stress applied to the material e is the strain corresponding to applied stress in the material