Second-Order Linear ODEs (Harmonic Oscillators, Damping & Resonance)
Underdamped, critically damped, and overdamped dynamical responses
Adjust the damping ratio ζ and natural frequency ω₀ in y'' + 2ζω₀y' + ω₀²y = 0 to see the oscillation envelope ±e^(-ζω₀t) control decay.
1. Characteristic Roots & The Damping Envelope
Substituting y = e^(rt) into ay'' + by' + cy = 0 yields the characteristic polynomial ar² + br + c = 0. Complex conjugate roots r = -α ± iω_d produce oscillations trapped inside the exponential envelope ±A e^(-αt).
r2+2ζω0r+ω02=0⟹r=−ζω0±ω0ζ2−1 Quick Reference & Cheat Sheet
Damping Regimes
ζ<1 (Underdamped),ζ=1 (Critically Damped),ζ>1 (Overdamped) Determines whether the system oscillates across equilibrium or decays monotonically.