reply to post by LucidDreamer85
If the standing wave is being created by reflection off of a wall the nodes will be horizontally distributed. Acoustical levitation requires that the
nodes be vertically distributed, the object gets "caught" between nodes.
In order to be levitated, the object has to be smaller than the wavelength of the sound. To give you a rough idea, to levitate a basketball a
frequency of 400Hz would have to be used. That's about a middle G note. No problem there but the amount of energy required would be huge. It takes
154 dB (a jet engine 100 feet away produces 140 dB) to levitate a water drop 1.4mm in diameter (about .15 gram) that basketball weighs 567 grams,
3,780 times as much. I don't think it can be done. I don't think there is a sound loud enough.
Reflecting sound waves does not amplify the energy. If you are talking about audio feedback, that requires an electronic amplifier.
[edit on 1/21/2010 by Phage]