Thus far we have concentrated analyses primarily on the transient dynamics of the system. The analyses in the prior chapter focused on characterizing the response over short periods where the system transitioned from one state of equilibrium to another. Some systems, however, operate for extended periods under dynamic load or input (e.g., cyclic loads) and do not settle to a fixed or constant equilibrium condition. For these systems, the transient response makes up a relatively small fraction of the pertinent dynamics we wish to analyze. An alternative formulation is necessary to examine such dynamics. Ask yourself the following:
B What is the steady-state response of a linear system excited by a cyclic or oscillatory input?