Materials key terms

elastic deformation

The temporary change in shape of a material when a force is applied, which returns to its original shape once the force is removed.

plastic deformation

The permanent change in shape of a material when a force is applied, which does not return to its original shape after the force is removed.

Hooke's Law

The principle stating that the force needed to extend or compress a spring by some distance is proportional to that distance, within the limit of proportionality.

Limit of Proportionality

The maximum extent to which a material can be stretched or compressed without permanently deforming, beyond which Hooke's Law no longer applies.

Force-Extension Graph

A graph that shows the relationship between the force applied to a material and the extension it undergoes.

Limit of Proportionality

The maximum extent to which a material can be stretched without deviating from Hooke's law.

elastic potential energy

The energy stored in a spring when it is compressed or stretched, calculated using the formula Ee = 0.5 x k x e^2, where k is the spring constant and e is the extension.

Hooke's law

A principle stating that the force needed to extend or compress a spring is proportional to the distance it is stretched or compressed, valid within the limit of proportionality.

Tensile Stress

Tensile stress is defined as the force applied per unit area of a material, calculated using the formula: tensile stress = force / area.

Tensile Strain

Tensile strain is defined as the extension per unit length of a material, calculated using the formula: tensile strain = extension / original length.

Young modulus

A measure of the stiffness of a material, defined as the ratio of tensile stress to tensile strain.

Tensile stress

The force applied per unit area of a material, calculated as stress = force / area.

stress

The force applied per unit area within materials, typically measured in pascals (Pa).

strain

The deformation experienced by a material in response to stress, defined as the change in length divided by the original length, expressed as a dimensionless ratio.

Young modulus

A measure of the stiffness of a material, defined as the ratio of tensile stress to tensile strain.

tensile stress

The force applied per unit area in a material, calculated as stress = force / area.