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Acoustic Levitation Works On Small Animals
anthemaniac writes "Researchers for at least two decades have used acoustic levitation to suspend light materials without a container. Wenjun Xie, a materials physicist at Northwestern Polytechnical University in China, has previously used ultrasound fields to levitate globs of iridium and mercury, very heavy materials. Now the scientist has performed the feat with live animals. From the story: 'Xie and his colleagues employed an ultrasound emitter and reflector that generated a sound pressure field between them. The emitter produced roughly 20-millimeter-wavelength sounds, meaning it could in theory levitate objects half that wavelength or less.' Apparently the ants, spiders and ladybugs endured the trick just fine, but the fish didn't do so well due to lack of water."
Funny, when I heard "small animal," I assumed something on the order of protozoa and bacteria. Something down where it's a little harder to discern from plantlife and viruses, unless you refamiliarize yourself with the actual criteria for the animal kingdom.
"Animals are a major group of organisms, classified as the kingdom Animalia or Metazoa. In general they are multicellular, capable of locomotion and responsive to their environment, and feed by consuming other organisms. Their body plan becomes fixed as they develop, usually early on in their development as embryos, although some undergo a process of metamorphosis later on. Biologically, human beings fall under the animal kingdom."
-- http://en.wikipedia.org/wiki/Animal[
Well, ultrasound is used to create the field... but the emitter that produces the waves for levitation has waves of much, much longer wavelength (and therefore much lower frequency). I think instead of at the molecular level, the concern would be at the macro level... that is, can animal tissue deal with rapid mechanical manipulation from the soundwaves?
And is it possible for animals to have cavities or structures with a resonant frequency equal to that of the emitted waves? That's where the real danger lies, I think.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Ehum, only if sound travelled 1 meter per second in air. Hint: it doesn't. It's more like 340, hence the frequency is 50 * 340 = 17,000 Hz.
They have magnetic levitation for fish and frogs.
A spider is an insect, not a aminal.
Actually it's an arachnid, not an insect.
(But I'd really like to know what an aminal is.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
it'd have to be lower... it said "half the wavelength", in TFA, assuming 2 meters for a person (thats a bit over), This site (http://www.sengpielaudio.com/calculator-wavelengt h.htm) suggests that 85.75hz is what is needed. Using 6 feet people (12 foot wavelengths), we get 93.8hz
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Connection too slow for X forwarding? Try "ssh -CX user@host"
So technically it IS an animal, and is closely related to crabs. .
If you are about to mod me down, keep in mind that this post was most likely sarcastic.
You're concerned about organisms that contain MORE water? The specific heat capacity of water is greater than that of most materials, seems to me that more water would be a good thing.
Sorry Missed the copyAndPaste of link, the right link is right link
I love deadlines. I like the whooshing sound they make as they fly by.
What would happen if you turned the device upside down and mounted to to the bottom of a platform or a car? Would it take too much energy?
Unless you had a very small car, absolutely nothing. It's got nothing to do with the amount of energy used, but the wavelength of the soundwaves used.
Just because you're paranoid doesn't mean there isn't an invisible demon about to eat your face
To me the video seemed like two tubes that generated a derivation from Bernoulli effect.
Some readers seem to mix up infra and ultra. Ultrasound is high frequency sounds.
References:
http://en.wikipedia.org/wiki/Bernoulli_Effect
http://en.wikipedia.org/wiki/Ultrasound