Stress vs Strain

—> tensile stress (stress) refers to the cause of a deformation and tensile strain (strain) refers to the effect of the deformation.

—> stress is the ratio of an applied force F to the area A over which it acts :

Stress = F/A
(units : Pa = N/m^2 = Nm^-2

—> strain is the relative change in the dimensions or shape of a body as the result of an applied stress :

—> The percentage of changes shape

strain = change in length/original length
(strain has no units)

—> a property of a material known as the Young’s modulus uses the ratio of stress and strain to determine how much a material with deform when stress is applied.

—> Young’s modulus is the ratio of tensile stress to tensile strain of a material while obeying Hooke’s law.

Young’s Modulus (E) :

E = stress/strain = F/A//△L/L = FL/A(△L)

(Pa) or FL/Ax