Before revision: Springs, which represent the elastic component of a viscoelastic material, obey Hooke's Law : where σ is the applied stress, E is the Young's Modulus of the material, and ε is the strain.
After revision: Springs, which represent the elastic component of a viscoelastic material, obey Hooke's law : where σ is the applied stress, E is the Young's modulus of the material, and ε is the strain.