Hiya can anyone show how to derive the euqation of damped frequency for a spring
ωd = ωnsqrt(1-ζ2)
What is the differential equation describing the motion?
Google will find lots of web sites with the derivation.
As NascentOxygen said, you write down the differential equation for simple harmonic motion with damping, and solve it. There are no "clever tricks" required.
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