Viscoelasticity can be mathematically represented with a Maxwell element, that consists out of a spring and a dashpot (or damper) put in series. The spring represents the elastic part with an elastic modulus, while the damper indicates the viscous part with a Newtonian viscosity.
For short times or high velocities, only the influence of the spring will be visible and the Maxwell element acts like an elastic solid.
For long times or low velocities, only the influence of the dashpot will be visible and the Maxwell element acts like a Newtonian liquid.
The mathematical function of the Maxwell element is given in the yellow box. Within the formula, the elastic modulus G0 and the Newtonian viscosity η0 can be recognised. Note that the modulus G0 divided by the viscosity η0 is defined as the relaxation time Ι0 of the material.