Tape that when the correct note is held at the right frequency for a couple of seconds, will vibrate itself loose.

Make it a note that is rarely heard or else it would come loose every time someone plays the cello. A special tool could produce the note.

Like how a wine glass can shatter.
-- DesertFox, Jun 23 2004

//a note that is rarely heard...//

"Dear Dad, please call me back when you get this note so I can pay you back all that money..."
-- robinism, Jun 23 2004


I think you will have trouble getting enough energy into the adhesive that way. Adhesive is so elastic that it dissipates energy easily and the damping spreads out any resonance.
-- kbecker, Jun 23 2004


What about the reverse? Adhesive that is activated by sound. Ultrasonic energy might be used to stimulate polymerization. I see potential applications in laminates. Where gaps of one wavelength would set up standing harmonic waves. I could see your idea working if the adhesive had, microspheres in it of certain diameter that would resonate and shatter. Thereby reducing the adhesives hold.
-- Spare parts, Jun 24 2004


I'm trying to imagine what in the bejezzus this HRA would be for. i can picture some rubeberg contraption involving taping a key to the inside of a door, so if you come home shitfaced or lost your key you can slide a paper under the door, belt out the note and your spare key will fall down and you can fetch it to let yourself in.

So if you want sonic key, that is if it's technically possible to make tape like that, probably easier to make a lock that springs open if you hit the right note. Right?

What did you want to do with this magic HRA tape?
-- igirl, Jun 24 2004


Good show, but don't hang too many pictures in one room with the same note.
-- Cheekio, Jun 24 2004


Flight TX245 broke apart at cruising altitude.
Unfortunately the white noise from air turbulence affected the adhesive.....
-- Ling, Jun 24 2004


[Spare parts] that would be sonic welding, which is widely known to exist.

[DF] Geckos exhibit some of these characteristics - as you all know, geckos, and lots of insect species, use attitudinal control of their foot-pad nano-scale setae and weak molecular attraction forces to 'stick' to surfaces. If you play certain frequencies at a gecko, it spasms, the attitude of the setae changes and it falls off the wall. Best done with a skin flute.
-- ConsulFlaminicus, Jun 25 2004



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