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The tweet, posted on September 1, 2011, by @qikipedia, read in its entirety: “It would take an elephant, balanced on a pencil to break through a sheet of graphene the thickness of cling film.” Some detective work revealed that the statement originated with mechanical engineering professor James Hone of Columbia University, who said in 2008, “Our research establishes graphene as the strongest material ever measured, some 200 times stronger than structural steel. It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap.”
The professor’s contention raises numerous questions, the first one being “What is graphene?” Microsoft Word doesn’t know—it keeps giving graphene the red squiggly underline, which means, “Surely you mean grapheme.” (I surely don’t, despite the fact that I’m littering this page with graphemes.)
Fortunately, the Wikipedia entry on graphene includes this definition from a paper by Andre Geim and Konstantin Novoselov, who won the 2010 Nobel Prize in Physics for their work on the miracle substance: “Graphene is a [sic] flat monolayer of carbon atoms tightly packed into a two-dimensional (2D) honeycomb lattice, and is a basic building block for graphitic materials of all other dimensionalities. It can be wrapped up into 0D fullerenes, rolled into 1D nanotubes or stacked into 3D graphite.” Picture chicken wire, but with each connection point being a carbon atom. The result of that mental metamorphosis is graphene. (Well, virtual graphene.)
Professor Hone has better things to do—such as figuring out how to layer enough sheets of graphene together to get it to be the thickness of Saran Wrap—than to deal with the rest of my questions. So I leave them to you, gentle reader. And away we go.
Is the pencil vertical or horizontal? Let’s assume vertical, so that the entire weight of the elephant is concentrated at a single point on the graphene. Other than for writing on a wall, a horizontal pencil is useless in most cases, including pencil cases.
What is the pencil made of? You can’t expect a regular old pencil to carry the weight of an elephant. The obvious answer is graphene, rolled into a massive nanotube. (Massive for a nanotube, regular size for a pencil.) The manufacturer could include a thin cylinder of graphite within the roll of graphene so that the pencil could actually be used to write, but that strikes me as pedantic. (Then again, if it can’t write, is it really a pencil? Perhaps not. I’ve been told that I can’t write, and I’m certainly not a pencil.)
Anyway, we have the graphene Saran Wrap and the graphene pencil. The next question is, How do you get the elephant onto the pencil? Wait a second, back up. Is it an African elephant, weighing in at, say, 15,000 pounds, or is it the more diminutive Asian elephant, tipping the scales at a more manageable 10,000 pounds?
The two creatures also have vastly different temperaments. You might get away with this stunt using an Asian elephant, but I’d stay away from trying to get an African elephant onto a pencil, especially a bull African elephant. He might not be able to break the graphene pencil, but he’ll almost certainly destroy the lab in his zeal to avoid being balanced on it.
Come to think of it, there’s a lot we don’t know about the elephant. Is it a full-grown elephant or a baby elephant? A baby Asian elephant is going to be the easiest choice to get onto the pencil. As it approaches the graphene, do the researchers play Henry Mancini’s “Baby Elephant Walk”? If not, why not? These opportunities don’t come along every day.
Will the weight of the baby elephant concentrated at the tip of the pencil be enough to pierce the graphene? If it was going to require the weight of an adult African elephant balanced on the pencil, I doubt the baby elephant, at about 230 pounds, has enough heft. So if you put the full weight of our adorable little elephant onto the superstrong nanotube pencil, I have to figure that, although the Saran Wrap might hold, the elephant won’t. The pencil will puncture the poor baby’s hide and get swallowed up. Now you have a wounded baby Asian elephant bleeding all over your graphene, a mother elephant going out of her mind and a protest by People for the Ethical Treatment of Animals.
Ultimately we’ll have to go with a full-grown Asian elephant, itself necessarily encased in a protective layer of graphene, situated above the graphene sheet, balanced on a graphene pencil. And unlike this entire column, it can’t be missing the point.
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11 Comments
Add CommentTalk about evading a point! I bet that elephant came from the circus and it was a tight-wire walker. Isn't it also true that if you put a layer of liquid salt on the graphene, it can become a super charged battery?
Reply | Report Abuse | Link to thisIf you can imagine that elephant on the point of a pencil, then you will have no trouble imagining this: Make the graphene 1" thick and spread liquid salt between the layers and build a floating city out on the ocean that can house at least 5 million people and businesses. You would have the world's largest electrical battery and clear up miles and miles of land that could be used to grow food and provide a game reserve. You could encase an air chamber that would keep the city afloat and a solar electric motor to keep the city from drifting into land. Israel developed a quad copter car that could use a graphene battery to power it and you could use that quadcar to fly to land when you needed to resupply your food or take a vacation away from the busy city.
There is a lot to say about the TV show "Stargate Alantis". I know a lot of people, including me, would love to live and work in a city like that. The strength of graphine could make that fictional city a reality. Imagine it if you can.
I have no idea what you are saying but there is no
Reply | Report Abuse | Link to thisdoubt in my mind that global warming is involved
JamesDavis, make that floating city a large datacentre using seawater for cooling and wave and solar for power and you might just be able to make a profit.
Reply | Report Abuse | Link to thisAre we trying to evade the point here?
Reply | Report Abuse | Link to thisFurther review shows that Hone has stated, in much clearer manner that "To put things in perspective: if a sheet of cling film (which typically has a thickness of around 100 µm) were to have the same strength as pristine graphene, it would require a force of over 20,000 N to puncture it with a pencil," he explained. "That is the force exerted by a mass of 2000 kg, or a large car!" (or the force exerted by an object around 4,500 lbs focused into a single point load) [physicsworld.com - http://physicsworld.com/cws/article/news/35055]
Given your numbers, a full grown elephant of either variety would probably be overkill, but does provide a reader a great mental image. Perhaps the elephant is balancing on one foot atop a very short pencil, so that all its weight is being applied to a single point without wrapping the poor thing in graphene! (Although getting an elephant to balance on a pencil is likely easier than getting a car to balance on a pencil if we want to continue to use the imagery).
Leaving that point behind, I must admit some curiosity to JamesDavis' comment about creating a super charged battery. If we're placing this floating city on the ocean, would that have enough salt content to power this battery, or would we need to add the extra liquid salt? Or perhaps we need to add less liquid salt? Oh the possibilities (and resulting questions, I like questions)!
I'm confused. Where does the elephant fit into the floating city? Is in an elephant city, or is there just a resident circus?
Reply | Report Abuse | Link to thisI appreciate the attempt to layman-ize the concept of Graphene, but this article reads like it was written by an overconfident adolescent. What's with all the pointless, witless filler? Seriously, SA... make this guy try harder.
Reply | Report Abuse | Link to thisI think the elephant just fell off the pencil and is floating out there in the ocean somewhere. Don't let those elephants, who can balance themselves on pencils confuse you...they are just show-offs.
Reply | Report Abuse | Link to thisTo "NekoMich"; I don't think ocean salt is the same kind of salt as liquid salt. When SciAm ran the article about graphene (or maybe it was cellophane) liquid salt batteries, they didn't tell how you make the liquid salt, but either way, it was a supercharge battery that could hold a tremendous amount of electricity. I think MIT may had designed that battery.
If you could layer the graphene over the cellophane liquid salt battery and turn that into a building; you'd never have to pay another electric bill again. I think they did something like that with that new bank they just built down in Georgia. The building is totally self-contained.
This... writing a complete waste.
Reply | Report Abuse | Link to thisMirsky must get paid by the word count. Nothing he had to say was remotely of value. I'm sure it was a very crude albeit failed attempt at humor, but he didn't even bother to get to the point. I'm disappointed with SA, I was hoping for a lay explanation of the incredible strength of Graphene and some of its obvious values. Try getting to the point next time.
Reply | Report Abuse | Link to thisI've been a subscriber to Scientific American for 25+ years. I don't remember exactly when Steve Mirsky came on board but I have been a fan of his work since first seeing it in SciAm. The Anti Gravity feature, along with the long defunct Connections feature, are my two all time favorite regular features ever in the magazine.
Reply | Report Abuse | Link to thisThat said I do have to to say that in a long list of entertaining articles Mirsky has written this one certainly ranks among the wittiest and funniest ones I've seen. Keep up the great work Steve.
Just a comment to some of the folks complaining here - this feature is supposed to be a humorous column (granted a science oriented humor column), so lighten up on the criticisms about not conveying scientific info. That's not the point. And yes it's OK to not think Mirsky is funny but a lot of us think he's quite entertaining. Humor is a very personal preference. Nobody forces you to read his column. If you don't think he's funny, don't read it.
So now I must come to the shocking realization that somewhere in this vast multiverse there is an elephant delicately balanced upon a graphene pencil writing the Bible on a sheet of graphene. This is very disturbing.
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