Ok, so what I'm getting from this article is that the water droplet is ejected from the oscillating surface at a greater speed(magnitude) than is provided by the wavelength of the oscillating surface; is this qualitatively different from the results of dropping a tennis ball/basketball stack? I mean, the article kind of put it's figurative finger on it when it made the tennis ball comparison. \: l

Ok, so what I'm getting from this article is that the water droplet is ejected from the oscillating surface at a greater speed(magnitude) than is provided by the wavelength of the oscillating surface; is this qualitatively different from the results of dropping a tennis ball/basketball stack? I mean, the article kind of put it's figurative finger on it when it made the tennis ball comparison. \: l

The droplets are vibrated at a different frequency then the vibrated surface apparently. In the case of the ball, the deformation is the result of forward momentum in the ball transferring to its circumference where the droplets are vibrated on a vibrated surface and are not hitting the surface with forward momentum.

If you vibrated your ball on a vibrating surface, then it would be qualitatively similar.

This phenomena is kind of interesting, but would be more interesting if the kinetic rate was greater than the system input energy.

The macro scale version of quantum scale Vavilov–Cherenkov radiation.

Cherenkov radiation is analogy of Mach shock wave/cone.

The droplets are vibrated at a different frequency then the vibrated surface apparently. In the case of the ball, the deformation is the result of forward momentum in the ball transferring to its circumference where the droplets are vibrated on a vibrated surface and are not hitting the surface with forward momentum.

If you vibrated your ball on a vibrating surface, then it would be qualitatively similar.

This phenomena is kind of interesting, but would be more interesting if the kinetic rate was greater than the system input energy.

The thing that makes me point toward the stacked tennis/basketball model is the article's image series indicating the surface is oscillating (undulating) vertically; this seems like it's just a rehashing of a relatively well-understood mechanical system...which brings to mind questions of whether there is 1000fps footage of the tennis/basketball stack drop demonstration. Perhaps the tennis ball behaves similarly to the drop of water?

-cont.-

Given that the surface is undulant (according to the photo-plate), it follows that the waveform propagating across the material creates the "basketball" (upward motion of mass as it conforms with the wave) causing the ejection of the "tennis ball" at X velocity relative to the energy imparted by the mass acting under the influence of the wave. I'm quite curious to see if there's a correlation between the behaviors of both systems.

On a sort of side-note, the article indicates the water droplet actually increases in speed (attributed to internal elasticity) after leaving the surface which seems to be a contradiction to standard ballistic calculations --i.e. the projectile leaves the propulsion source and that's the end of it, it's all dissipation of velocity thereafter. Definitely a puzzler....