How do we measure the elasticity of materials?

The elasticity of materials is typically measured using stress-strain testing, which involves applying a force to a material and measuring the resulting deformation. The stress is calculated as the force applied per unit area, while strain is the ratio of the change in length to the original length. The elastic modulus, often referred to as Young's modulus for tensile stress, is derived from the linear portion of the stress-strain curve and represents the material's ability to deform elastically when a load is applied. Other types of elasticity, such as shear and bulk modulus, can be measured similarly by applying different types of stress.