The system examined here is similar to that of VM90, except that three dampers have been added:

Figure 1: Two Mass-Spring-Damper System Problem Sketch

A harmonic analysis is first performed with force (F1 sin ωt) acting on mass m₁. Over a cycle, the average, amplitude, peak, phase of the stiffness and kinetic energies, as well as the damping energy and work of the external force are determined.

The corresponding transient analysis is also performed. The load varies harmonically as a function of time and the initial conditions are zero. From the steady-state parts of the responses, the energy and work quantities are extracted to compare with the values obtained from the harmonic analysis.