Beulah, Peel Me a Piece of Copy Paper

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The surprisingly rich physics of peeling paper

[T]he physics of peeling paper almost exactly mimics the stick-slip movement of tectonic plates, right down to the statistics of the time between “quakes” and the correlations between released energy and aftershock activity.

From the preprint, “Line creep in paper peeling:”

For paper, we use perfectly standard copy paper, with an areal mass or basis weight of 80 g/m2. Industrial paper has two principal directions, called the “Cross” and “Machine” Directions (CD/MD). The deformation characteristics are much more ductile in CD than in MD, but the fracture stress is higher in MD [20]. We tested a number of samples for both directions, with strips of width 30 mm. The weight used for the creep ranges from 380 g to 450 g for CD case and from 450 g to 533 g for MD case.

I’ll never look at copy paper the same way again.

It'll Do, But I Wanted a Frikkin' Laser

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An electric fly-swatter, over at Built on Facts

Press the button on the side and swing it at the fly in the air; there’s a spark and a pop, and the fly falls out of the sky like a little brick. No mess, and dementedly entertaining (I’ll admit it). Yeah it’s a little redneck, but effectiveness is effectiveness.

Redneck? Surely you jest. What is needed now is a little empirical testing, a la Colbert’s fun with a spark coil.

Safety Tips

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As if a physicist fence could keep us out or in.

He informs me that it is actually a “physicist fence” which is used to keep the physicists on campus and prevent them from roaming free in the community and administering random physics lessons to unsuspecting citizens.

Don’t forget: we know how to tunnel. We learn that in quantum mechanics.

No, the best way to keep us from administering random physics lessons is to provide us with fun toys like lasers and vacuum systems to keep us occupied, to not make eye contact, and say nothing to encourage us (questions or leading statements).

True story: last week, out at lunch, one of the gang (not a physicist) got two containers of cream for his coffee. He mused, out loud, “I wonder if they have the same volume?” He then emptied one into his cup, and put the other one down! How do you ask the question and then not follow through? I opened the second and emptied it into the first, and confirmed that they were the same volume.

So, avoid things like that, or “I wonder how that works,” or baiting us with obviously wrong statements (“It swirls that way because of the Coriolis force” or “Relativity is crap”). And don’t attempt nerd sniping.

About That New "Theory" of Yours . . .

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Outsider Science

To merit their attention, professionals say, an outsider would have to show that he’s done his homework. Serious contenders have to understand the language of physics and get their math right. Most importantly, any new theory must agree with past experiments.
[…]
Frustrated amateurs can be aggressive, clamoring to have their ideas heard. Not surprisingly, physicists are more receptive to polite questions than to lengthy treatises accompanied by angry rants, and if the science is solid, they may listen.

To this I would add, you have to make sure it’s science to begin with.

via physics and physicists

That's Going to Leave a Mark

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Pat Metheny on Kenny G

I first heard him a number of years ago playing as a sideman with Jeff Lorber when they opened a concert for my band. My impression was that he was someone who had spent a fair amount of time listening to the more pop oriented sax players of that time, like Grover Washington or David Sanborn, but was not really an advanced player, even in that style. He had major rhythmic problems and his harmonic and melodic vocabulary was extremely limited, mostly to pentatonic based and blues-lick derived patterns, and he basically exhibited only a rudimentary understanding of how to function as a professional soloist in an ensemble – Lorber was basically playing him off the bandstand in terms of actual music.

But he did show a knack for connecting to the basest impulses of the large crowd by deploying his two or three most effective licks (holding long notes and playing fast runs – never mind that there were lots of harmonic clams in them) at the key moments to elicit a powerful crowd reaction (over and over again). The other main thing I noticed was that he also, as he does to this day, played horribly out of tune – consistently sharp.

That’s just the warmup.

Hitchcock Goes To Mars

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NASA preps for ‘7 minutes of terror’ on Mars

[T]hey have to get the lander on the ground, and that’s where the worry comes in. In fact, they have a name for it in the Mars exploration community: “seven minutes of terror.”

Seven minutes is all it takes for a spacecraft travelling neary 13,000 miles per hour to hit the Martian atmosphere, slam on the brakes and reach the ground.

And then there’s this tidbit, with the resulting obligatory snark:

Historically, 55 percent of Mars missions have ended in failure.

I’ll bet the odds go up when you don’t mix up metric and English units.

——

Good luck to them.

UPDATE: SUCCESS! Animation of the landing and some subsequent operations