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Education Science

5 Strangest Materials 196

MattSparkes writes to tell us that NewScientist recently posted a quick look at five interesting materials with some very strange properties. There are liquids you can walk on, liquids that will escape containers by creeping up the sides, and magnetic liquids that can easily show you the shape of magnetic fields. The story also offers video links to display some of more amazing properties described.
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5 Strangest Materials

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  • by Anonymous Coward on Wednesday January 03, 2007 @07:20PM (#17451906)
    "Fall heavy towards the moon, and the moon falls also towards you." -- Nietzsche

    Hammer and feather are dropped simultaneously from equal heights (as measured by distance from the center of the moon), separated laterally by a distance substantially less than the moon's diameter. Both hammer and feather experience force from the moon's gravity proportional to their mass, and hence both accelerate at the same rate. Meanwhile, the moon is also accelerating towards the other two objects, but unevenly so: the hammer exerts a greater gravitational pull due to its greater mass. The moon is therefore subject to a torque, causing it to accelerate more rapidly towards the hammer.

    The hammer is first to hit the ground.

    Anyone who denies this truth is a spatially absolutist lunocentric whose refusal to recognize the validity of hammer/feather mechanics places him wholly beyond the help of Galilean metaphysics. Such hammer/feather rejectionists ought to be banished to the stars, for their own good and for the good of not only hammers and feathers but all subjugated smaller objects, everywhere, who find themselves victims of this scientifically perpetrated emassculation.

  • by Phrogman ( 80473 ) on Wednesday January 03, 2007 @07:25PM (#17451942) Homepage
    It was the first thing that came to mind when I saw the demo of the people running over the water like that...
  • by tha_rippa1be ( 1045068 ) on Wednesday January 03, 2007 @07:47PM (#17452152)
    At the end of this video there is a short part about the fluid going upwards. http://web.ujf-grenoble.fr/PHY/FOREXPER/TPhelium/p ages/Presentation%20film.html [ujf-grenoble.fr]
  • by Mattcelt ( 454751 ) on Wednesday January 03, 2007 @07:47PM (#17452156)
    I'm embarrassed to admit this, but I can't tell if your post is hyperbole or not.

    So straight up - does the hammer really hit the ground first? Replacing the hammer and feather with larger bodies - say, one (as the hammer's stand-in) which is the same mass as the moon, and the other (the feather's double) which is 1/10th the mass of the moon, it seems obvious that the more massive body will impact first, as it does have a significantly larger bearing on the moon.


    Does the hammer's insignificant size relative to the moon negate any realistic gravitational influence it may have? Or for that matter, does the term 'significantly larger' really apply to the hammer and feather?

    I think the 3-body dynamics may be so small at that scale as to be nearly nullified - I would suspect that the gravitational pull of the hammer on the moon would move it less than the diameter of an atom required to change the timing of the impact of the two objects. [Unless one is counting the impact of the electron shells prior to the impact of the nucleus, in which case I suspect the preponderance of heavier (atomic weight-wise) elements in the hammer, with correspondingly more electrons, necessitating population of the "larger" d- or f-shells, would be first. But again, it's not the gravitational influence of the mass of the hammer that would be the deciding factor...]

    So.... anybody care to do the math?
  • by Anonymous Coward on Wednesday January 03, 2007 @07:48PM (#17452164)
    They left out elastic fluids, such as a mixture of high molecular weight polyethylene oxide in water. Once the fluid begins to pour out of its container, it will partially empty the container, even if righted. This is the open siphon effect. If while pouring out the fluid, you cut it with scissors, the fluid will snap back into the beaker like a rubber band. This can all be done at room temperature.

    What makes this happen is the high molecular weight polyer. The molecules become entangled, and when poured, they pull each other along, resulting in the emptying of the container.

    These fluids also exhibit other interesting behaviours, such as the Weissenberg effect, where when rotating rod is placed in the fluid, the fluid climbs up the rod. Also, add some particles (or bubbles), start stirring, then suddently remove the stirring rod, you will see the fluid snap back when it comes to rest.
  • by Gat0r30y ( 957941 ) on Wednesday January 03, 2007 @07:56PM (#17452244) Homepage Journal
    Funny note: as i was looking for the thermodynamic properties of plutonium, ebay promised to make me a great offer on it. Seriously, like ice it will expand and get less dense as it drops in temperature. Only, instead of just the one phase change, there are many. Unfortunately, this [llnl.gov] is the best I can find for a phase diagram. In thermo, my prof put up a much nicer one, just trust, the phase diagram is pretty crazy looking.
  • by jpellino ( 202698 ) on Wednesday January 03, 2007 @08:05PM (#17452324)
    ... you have to mix the non-newtonian fluid pretty accurately - too thin and it won't support you, too thick and it's trivial... you'll notice they have a stirrer of some sort in the pool video - this is important - this stuff can settle in short time so you end up with mostly water above and mostly cornstarch below. Jearl Walker once lept over tables into a feed trough full of this stufff on his show. He didn't splash a drop. He did, however lose his balance, and tipped the whole thing which slowly flowed into the audience...

    And they mention conrflour - I'd stick with cornstarch. One time going France and Hungary to teach science, I figured I'd forego the big containers of white powder on the international flights... and getting to Nice, I found that you can only buy boxes of cornflour, not boxes of cornstarch in French grocery stores. You could get sugar-packet sized envelopes of it, which were labeled in French with something I could not read but I imagine said "You are in France. We are famous of our sauces. If you need cornstarch to make a sauce, then go away!."

  • by Dadoo ( 899435 ) on Wednesday January 03, 2007 @09:33PM (#17453048) Journal
    Yeah, but water is one of the few (only?) materials whose liquid is denser than its solid and, as a result, freezes from the top down, rather than the bottom up. That's pretty strange, in my book.

    It also has one of the highest specific heats of any material. (Highest of any common material.)
  • Re:Aerogel (Score:4, Interesting)

    by kaszeta ( 322161 ) <rich@kaszeta.org> on Wednesday January 03, 2007 @11:01PM (#17453680) Homepage
    I always thought aerogel was some pretty cool stuff. If you insulated your house with it, you would only need one candle to keep the entire house warm. :)

    It's not quite that magical. A two inch layer of aerogel will keep things about as insulated as a really good vacuum thermos, however.

    I know, I work with the stuff on a regular basis, we use it as insulation, by the 400 liter barrel. See some of my pics of some of the solid slabs I have in the office [flickr.com].

  • by trentblase ( 717954 ) on Thursday January 04, 2007 @01:43AM (#17454872)
    You can also suspend a frog in a strong magnetic field because water is diamagnetic. http://www.hfml.ru.nl/froglev.html [hfml.ru.nl]
  • by Anonymous Coward on Thursday January 04, 2007 @02:00AM (#17454970)
    Yup, cooking from scratch is definitely the way to go. If you're looking to diet, I recommend spicy foods. Capsacin irritates the stomach lining and makes you feel more full. And spicy food is tasty too.

    Me, I just make 10 bean and cheese burritos every week. Made with organic beans. onions, olive oil, cheese, green chile, habanero, sour cream, and tortillas. Cook once and freeze.

    Then I cook other home made foods if I feel like it, or just eat a burrito if I'm feeling lazy.
  • 1. Dilatants (Score:3, Interesting)

    by _newwave_ ( 265061 ) <[vt.reklawluap] [ta] [todhsals]> on Thursday January 04, 2007 @02:11AM (#17455034)

    fluids that get more solid when stressed. The classic example is a mixture of cornflour and water - it's runny until you hit it when it becomes solid.

    I remember playing with this mixture in grade school and since then I have always wondered why materials like this could not be used to make protective/bullet proof armor. Could someone explain this to me?

  • empty calories (Score:3, Interesting)

    by ukemike ( 956477 ) on Thursday January 04, 2007 @03:44AM (#17455374) Homepage
    60 calories and 0 nutritional value. How is that a good thing? Wonder bread is to wheat as high fructose corn syrup is to corn. Wonder has almost no fiber. It is almost pure starch which is quickly converted into sugar in you digestive system. If you have low blood sugar and need a boost NOW eating a slice of wonder is faster than eating a powered sugar donut.

You will never amount to much. -- Munich Schoolmaster, to Albert Einstein, age 10