The purpose of this study is to analysis the viscoelastic models under dynamic loading. A five-parameter model is chosen for study exhibits elastic, viscous, and retarded elastic response to shearing stress. The viscoelastic specimen is chosen which closely approximates the actual behaviour of a polymer. The module of elasticity and viscosity coefficients are assumed to be space dependent i.e. functions of ' ' x in non-homogeneous case and stress-strain are harmonic functions of time ' ' t . The expression for relaxation time for five parameter viscoelastic model is obtained by using constitutive equation. The dispersion equation is obtained by using Ray techniques. The model is justified with the help of cyclic loading for maxima or minima.
Kakar et al. (Tue,) studied this question.