It does have a simple cause...Evey container, a room or concert hall for example, has what's called a simple harmonic. The note that will have a wavelength exactly twice the length of the room. When that note is truck one half a wave fills the room and the room vibrates to the 'simple harmonic'. Best place to try it, snd it's why singing there is soo much fun, is the bathroom.
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Thu 30 Oct 2003, 10:50,
archived)