Let the initial conditions be and . The velocity-impulse response of a damped oscillator is
All curves start at the origin with the same positive slope . Underdamping gives a decaying sequence of positive and negative lobes. Critical damping gives one positive lobe followed by return to zero. Overdamping also remains positive for these initial data, but has a longer tail. The initial impulse changes velocity abruptly, not displacement.
Figure 1.
Calculated displacement after the same initial velocity impulse for underdamped, critically damped and overdamped oscillators
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