September 18, 2012 at 5:45 pm

Video: Watch Sound Levitate Water Droplets

acoustic levitator water droplets

This week, we’ve seen swings that play music on the streets of Montreal and a dress called the Ruffletron, a futuristic musical instrument that makes beautiful music when touched — and that’s not even counting the squid that was a music visualizer app. Is everything turning into apps?

Now comes news from Argonne National Laboratory (via NBC) that scientists have figured out how to make water droplets just sit there in the air by creating a so-called “standing wave” of sound. Here’s how it works, courtesy of ANL:

The acoustic levitator uses two small speakers to generate sound waves at frequencies slightly above the audible range — roughly 22 kilohertz. When the top and bottom speakers are precisely aligned, they create two sets of sound waves that perfectly interfere with each other, setting up a phenomenon known as a standing wave.

At certain points along a standing wave, known as nodes, there is no net transfer of energy at all. Because the acoustic pressure from the sound waves is sufficient to cancel the effect of gravity, light objects are able to levitate when placed at the nodes.

What’s going on in the world? Here’s the video:

YouTube Preview Image

The point of this technology, as NBC explains, has something to do with convincing solutions to be more likely to become crystals by allowing them to evaporate without touching anything, which will apparently have all sorts of health benefits. Be that as it may, this is also just plain neat.

(Image courtesy of the Argonne video)