ABSTRACT
The dynamic behavior is of interest since viscoelastic materials are used in situations in which the damping of vibration or the absorption of sound is important. One can also consider the dynamic behavior in the compliance formulation. This chapter examines the mechanical damping as it relates to the storage and dissipation of energy. It develops simple expressions for the rigidity at resonance and determines the width of the resonance curve under the assumption of small loss. In the study of a system near resonance, it may be expedient to ignore the frequency dependence of tan δ provided that its magnitude is small. In nonlinear solids it is more sensible to speak directly of energy dissipation per cycle. In wave propagation, the loss tangent is associated with attenuation of waves. The chapter considers a ratio of energies so that the modulus will not appear in the final result in any case.
