Retrospectacle: A Neuroscience Blog

Vibration Meets Cornstarch, Hole-arity Ensues

Posted by Shelley Batts on March 1, 2007
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This is so unbelieveable, I had to watch it twice. Needless to say, cornstarch water behaves very strangely when shaken (but not stirred) by high-speed vibrations. The result are faraday waves.

Faraday waves are nonlinear standing waves that appear on liquids enclosed by a vibrating receptacle. They are named after Michael Faraday, who first described them in an appendix to an article in the Philosophical Transactions of the Royal Society of London in 1831.

If a layer of liquid is placed on top of a vertically oscillating piston, a pattern of standing waves appears which oscillates at half the driving frequency. These waves can take the form of stripes, close-packed hexagons, or even squares or quasicrystalline patterns.

The phenomenon has been described and published in 2004 by a group at the University of Texas, Austin.

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Comments

  1. #1 SciencePunk
    March 1, 2007

    I love this video! YouTube also has some great footage of rice arranging itself into Chladni patterns which is equally spectacular.

  2. #2 Blake Stacey
    March 1, 2007

    My friends used to do these tricks with oobleck in their dining room (all you need to get true weirdness is a paint mixer).

  3. #3 J-Dog
    March 1, 2007

    This is WAY cool! Do you think we could do this at home
    without a paint mixer? And what would be the best mixture?

  4. #4 sean
    March 1, 2007

    Mmm, ooblik… I ran across this video awhile ago, and it led eventually to something even cooler, though far less scientific: ooblik racing!

    http://www.youtube.com/watch?v=f2XQ97XHjVw

  5. #5 Kurt
    March 1, 2007

    Of course, the other thing that cornstarch water is known for is that if you strike it with enough force it acts like a solid, but if you press on it gently it gives way like a liquid. Here’s a somewhat silly YouTube demonstration…

  6. #6 Kurt
    March 1, 2007

    Arrg! Someone beat me to it!

  7. #7 J-Dog
    March 1, 2007

    Thank you all for the hints… Looks like I have some research to do….

  8. #8 darkman
    March 1, 2007

    i think it is time to market new wave lava lamps. these things could rock with colored cornstarch waves. i’m gonna get right on this.

  9. #9 Eric Juve
    March 1, 2007

    At 120hz I think it would make a somewhat irritating lamp to have nearby. I want to do this anyway, I think I will start with a DC motor with a off center weight. Should work.

  10. #10 Uri
    March 10, 2007

    Cool!