Builder Blames Navy as Brand-New Warship Disintegrates
There are technical terms for this kind of disintegration. Austal USA, Independence’s Alabama-based builder, calls it “galvanic corrosion.” Civilian scientists know it as “electrolysis.” It’s what occurs when “two dissimilar metals, after being in electrical contact with one another, corrode at different rates,” Austal explained in a statement.
A reason you aren’t supposed to mix aluminum and copper wiring in your abode.
If you have yet to run across posts on elevatorgate/rebeccapocalypse (over 9,000 Google hits on the former term) then you probably don’t read many science/skeptic blogs. If you have and are sick of it, don’t worry, because I’m not going to add my quanta of coinage. I have come to loathe participating in internet discussions of this ilk — despite the community supposedly being held among the science/skeptic minded, they have a tendency to stray from rationality and civility far too quickly and too much in magnitude for my taste. In many cases, if you don’t present the right answer™ as determined by the owner of the dais, you are quickly dogpiled into oblivion, and that can extend to any kind of criticism. Point out someone has misquoted Evil Protagonist (or note that EP was actually correct in some statement) and all of the sudden you are a staunch supporter of Evil Protagonist in the eyes of some (many?) participants.
However, in case you want more of the same or are otherwise interested in a somewhat related topic, here is a post by xkcd’s Randall Monroe on Google+’s insistence on publicly disclosing your gender, which does not seem to have descended into the usual quagmire, though it does include the predictable “it doesn’t bother me so it shouldn’t bother anybody” responses.
The bottom line is that there are a lot of reasons Google+ would want to ask about your gender. But there’s no good reason to pointedly make it the only thing in your profile that can’t be private—and many reasons not to, starting with basic courtesy. It may be a small issue in the grand scheme of things, but I think it’s worth getting right.
That would be a pentagaffe
Meet Your Sponsor: Metro Diverse Service’s Panterragaffe: A Pedal-Powered Walking Machine
Panterragaffe is a pedal powered two person walking machine, a walking bicycle. The name has a few elements to it. It’s a play on pantograph, which is a mechanism for copying drawings, since it’s similar to the leg mechanism. Also; Pan – all or spanning. Terra – earth. Gaffe – an unintentional act causing embarrassment to it’s originator or just goofy-ness. A bit of goofy-ness for everybody. To most people the name doesn’t mean anything, therefore its meaning is flexible.
North American detail map of Flickr and Twitter locations
Red dots are locations of Flickr pictures. Blue dots are locations of Twitter tweets. White dots are locations that have been posted to both
The meandering instability of a viscous thread
A viscous thread falling from a nozzle onto a surface exhibits the famous rope-coiling effect, in which the thread buckles to form loops. If the surface is replaced by a belt moving with speed U, the rotational symmetry of the buckling instability is broken and a wealth of interesting states are observed
You can do more than roll them down an inclined plane.
Soft-drink cans beat the diffraction limit
The group generated audible sound from a ring of computer speakers surrounding the acoustic ‘lens’: a seven-by-seven array of empty soft-drink cans. Because air is free to move inside and around the cans, they oscillate together like joined-up organ pipes, generating a cacophony of resonance patterns. Crucially, many of the resonances emanate from the can openings, which are much smaller than the wavelength of the sound wave, and so have a similar nature to evanescent waves.
To focus the sound, the trick is to capture these waves at any point on the array.
The best intro book for any topic
Of course I checked out physics and in addition to Larry Gonick’s The Cartoon Guide to Physics, it gave a bunch of books on various topics within physics. I have read none of these books, so I have no basis for endorsing or disputing the choices; I don’t know if “Best Intro” means they were going for pop-sci books for a general audience or intro textbooks for the student or serious amateur. The Cartoon Guide might indicate one way — I’m not sure — but the other titles are or seem more like textbooks. The closest I can come to a recommendation is noting that the QM book is by David J Griffiths, I’ve heard good things about it, and his Electrodynamics textbook is very good.
EIA Report: Renewables Surpass Nuclear Output
Let’s start out with the bad and misleading.
Looking at all energy sectors (e.g., electricity, transportation, thermal), production of renewable energy, including hydropower, has increased by 15.07 percent compared to the first quarter of 2010, and by 25.07 percent when compared to the first quarter of 2009. Among the renewable energy sources, biomass/biofuels accounted for 48.06 percent, hydropower for 35.41 percent, wind for 12.87 percent, geothermal for 2.45 percent, and solar for 1.16 percent.
Biofuels, unfortunately, includes ethanol. In fact, it’s probably mostly ethanol and if ethanol production represents a net gain in energy over the energy used to make it, it’s by a very slim margin. Not only do we mandate its production and inclusion in gasoline in the US, it’s also subsidized (the good news is that the subsidy is scheduled to end, and there’s a chance it won’t be renewed) and diverting land use to corn for ethanol has driven food prices up. Touting a huge increase in the production of ethanol is not good, and it really shouldn’t count as energy production.
I’m not sure where all the additional hydro power is coming from, though. If it’s a rebound in areas that were previously seeing droughts and production is just a return to the norm (or a spike from e.g. above-average snowmelt) then it’s a little misleading as well.
But there is good news:
In terms of actual production, renewable electrical output increased by 25.82 percent in the first three months of 2011 compared to the first quarter of 2010. Solar-generated electricity increased by 104.8 percent, wind-generated electricity rose by 40.3 percent, hydropower output expanded by 28.7 percent, and geothermal electrical generation rose by 5.8 percent. Only electricity from biomass sources dropped — by 4.8 percent. By comparison, natural gas electrical output rose by 1.8 percent and nuclear-generated electricity increased by only 0.4 percent while coal-generated electricity dropped by 5.7 percent.
We are installing solar and wind, and coal use went down. Yay!
Rotating cylinder puts a new spin on slow light
In 1859 the French physicist Hippolyte Fizeau demonstrated this “photon drag” in the longitudinal direction by shining light through flowing water. More than 100 years later, in 1976, the British physicist Reginald Jones demonstrated it similarly in the transverse direction, by shining light near the edge of a spinning glass disc. But until now, it seems, no-one has ever shown that an image formed by light can be rotated. The problem is that the atoms are so quick to re-emit absorbed photons that the change in an image’s rotation is barely perceptible.
via Zapperz