⛓️ Hanging Chain 3D Physics Simulation: Bessel Normal Modes, Resonance and Whirling (2D)

A heavy chain hangs from a shaken pivot. Tune the pivot to a normal mode and the chain resonates in the shape of a Bessel function; shake in a circle and it whirls; sweep the frequency and see the peaks line up with the zeros of J0, with the 40-bead model checked against theory.