Pendulum

A real damped pendulum with air and bearing drag, not frictionless. Pull, release, and it gradually settles. The restoring force and damping look like:

$$\theta'' = -\frac{g}{L}\sin\theta - b_1\dot\theta - b_2|\dot\theta|\dot\theta$$

The linear term is viscous drag; the quadratic term kicks in at higher speed. Switch between Earth, Moon, and Jupiter to feel how $g$ changes the swing before it stops.