Perturbations

At first glance, today’s video appears to have little to do with fluid dynamics since it’s a demonstration of interactions between magnets. But for those who’ve delved into the mathematics of fluid dynamics — especially subjects like perturbation theory — there’s a lot to appreciate here. In the video, we see systems of magnets constructed and then manipulated, often by moving a single magnet and watching how the rest respond. Visually, this demonstrates how disturbances move in complex, interconnected damped systems. The auditory component — definitely turn the sound on for this video — is an extra layer of fluids-related goodness that also shows how reconfiguring a system changes its resonant frequencies. (Image and video credit: Magnetic Tricks and Magnetic Games; via Colossal)