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On Being has a nice little archive of rare audio clips from Albert Einstein, speaking on various subjects, including what it means to be American, E=MC^2, Gandhi, and "The common language of science."
((Photo: Einstein sitting on the front steps of his home in Princeton, wearing his fuzzy slippers. Photo courtesy of Gillett Griffin.) )
Chalk this up under "Blogs You Ought to be Following". The Tumblr Fuck Yeah Fluid Dynamics is a great place to find succinct, clear explanations of the forces that make things flow. In particular, they're fantastic at posting explanations behind things you see in YouTube videos, both viral and obscure.
The video above — in which a nice Siberian guy tosses boiling water off his balcony and creates a cloud of snow — has been making the rounds recently. Here's how Fuck Yeah Fluid Dynamics explains it:
Several effects are going on here. The first thing to understand is how heat is transferred between objects or fluids of differing temperatures. The rate at which heat is transferred depends on the temperature difference between the air and the water; the larger that temperature difference is the faster heat is transferred. However, as that temperature difference decreases, so does the rate of heat transfer. So even though hot water will initially lose heat very quickly to its surroundings, water that is initially cold will still reach equilibrium with the cold air faster. Therefore, all things being equal, hot water does not freeze faster than cold water, as one might suspect from the video.
The key to the hot water’s fast-freeze here is not just the large temperature difference, though. It’s the fact that the water is being tossed ...
The good folks on the most-excellent BBC Radio/Open University statistical literacy programme More or Less decided to answer a year-old Reddit argument about how many Lego bricks can be vertically stacked before the bottom one collapses.
They got the OU's Dr Ian Johnston to stress-test a 2X2 Lego in a hydraulic testing machine, increasing the pressure to some 4,000 Newtons, at which point the brick basically melted. Based on this, they calculated the maximum weight a 2X2 brick could bear, and thus the maximum height of a Lego tower:
The average maximum force the bricks can stand is 4,240N. That's equivalent to a mass of 432kg (950lbs). If you divide that by the mass of a single brick, which is 1.152g, then you get the grand total of bricks a single piece of Lego could support: 375,000.
So, 375,000 bricks towering 3.5km (2.17 miles) high is what it would take to break a Lego brick.
"That's taller than the highest mountain in Spain. It's significantly higher than Mount Olympus [tallest mountain in Greece], and it's the typical height at which people ski in the Alps," Ian Johnston says.
"So if the Greek gods wanted to build a new temple on Mount Olympus, and Mount Olympus wasn't available, they could just - but no more - do it with Lego bricks. As long as they don't jump up and down too much."
After you drink some Scotch, there's usually a thin film of the liquor left clinging to the bottom and sides of the glass. If you leave it out overnight, it'll dry and be a pain to wash off in the morning. But the same dried booze leavings can also be the beginnings of some really lovely art.
Ernie Button takes photos of the waving, swirling patterns left behind on Scotch glasses. This one — part of a series called Vanishing Spirits — is a picture of glass that once held a nice measure of Balvenie.
The idea for this project occurred while putting a used Scotch glass into the dishwasher. I noted a film on the bottom of a glass and when I inspected closer, I noted these fine, lacey lines filling the bottom. What I found through some experimentation is that these patterns and images that can be seen are created with the small amount of Single-Malt Scotch left in a glass after most of it has been consumed. It only takes a very thin layer of Scotch to create; the alcohol dries and leaves the sediment in various patterns. It’s a little like snowflakes in that every time the Scotch dries, the glass yields different patterns and results. I have used different colored lights to add 'life' to the bottom of the glass, creating the illusion of landscape, terrestrial or extraterrestrial.
Interestingly, there was a recent article that was published in the Journal of Nature (I think) by Dr. Peter Yunker on the Suppression of the Coffee-Ring Effect by Shape-Dependent Capillary Interactions i.e. how are coffee rings made. I contacted him to see if he could see any obvious connection between the two liquids and the rings / patterns they create. He got back to me and unfortunately could not explain what was happening with the Scotch.
That paper Button mentioned was published in 2011. It explores the physics of particles suspended in liquid — not just coffee, but lots of things. Turns out, if you put a drop of liquid on a solid surface, it will tend to dry in a circular shape. As it dries, anything suspended in the liquid will migrate to the outside of the circle. If you put a drop of coffee on a table and leave it to dry, what you'll get is a round spot ringed by a narrow band of dark coffee gunk.
Why does the gunk form a ring, instead of evenly covering the whole circle? Yunker's research showed that it has to do with the shape of the particles that make up the gunk.
Read the rest
MIT researchers developed a game that simulates the weird relativistic effects of slowing down the speed of light.
A Slower Speed of Light is a first-person game prototype in which players navigate a 3D space while picking up orbs that reduce the speed of light in increments. Custom-built, open-source relativistic graphics code allows the speed of light in the game to approach the player's own maximum walking speed. Visual effects of special relativity gradually become apparent to the player, increasing the challenge of gameplay. These effects, rendered in realtime to vertex accuracy, include the Doppler effect (red- and blue-shifting of visible light, and the shifting of infrared and ultraviolet light into the visible spectrum); the searchlight effect (increased brightness in the direction of travel); time dilation (differences in the perceived passage of time from the player and the outside world); Lorentz transformation (warping of space at near-light speeds); and the runtime effect (the ability to see objects as they were in the past, due to the travel time of light)."A Slower Speed of Light"
It can be a nice breeze, or a destructive storm, but either way wind is just moving air. And moving air is just moving molecules.
In an explainer for kids that's actually pretty helpful for grown-ups, too, Matt Shipman reminds us that the air around us isn't totally weightless. It weighs something, because molecules all weigh something:
They don't weigh very much (you couldn't put one on your bathroom scale), but their weight adds up, because there are a LOT of molecules in the air that makes up our atmosphere. All of that air is actually pretty heavy, so the air at the bottom of the atmosphere (like the air just above the ground) is getting pressed on by all of the air above it. That pressure pushes the air molecules at the bottom of the atmosphere a lot closer together than the air molecules at the top of the atmosphere.
And, because the air at the top of the atmosphere is pushing down on the air at the bottom of the atmosphere, the air molecules at the bottom REALLY want to spread out. So if there is an area where the air molecules are under high pressure (with a lot of weight pushing down), the air will spread out into areas that are under lower pressure (with less weight pushing down).
If you think Einstein-with-his-tongue-out is the last word in whimsical physicist photography, have a look at this 1931 shot of the Mighty Hip Einie with an Einstein marionette.
Here's the runner up: Einstein in fuzzy slippers.
Attributed to Harry Burnett while Yale Puppeteers were working in their theater, Teatro Torito, on Olvera Street in Los Angeles, California, circa 1931. The photo was taken by Harry Burnett at Cal Tech in Pasadena where Albert Einstein was teaching. Einstein saw the puppet perform at the Teato Torito and was quite amused. He reached into his jacket’s breast pocket, pulled out a letter and crumpled it up. Speaking in German, he said, “The puppet wasn’t fat enough!” He laughed and stuffed the crumpled letter up under the smock to give the puppet a fatter belly. This is a wonderful photograph that Harry treasured. Harry Burnett also kept the letter in a frame and loved to retell the story and at the end give his pixish laugh.
Pretty much everyone — including, probably, you — thought that the 2012 Nobel Prize in physics would go to the people who discovered evidence of a particle that meets the description of the theoretical Higgs Boson.
But, it didn't.
Instead, the winners are Serge Haroche and David Wineland, two physicists whose work is all about the way that photons — the tiniest pieces of light, which simultaneously behave as both shifting waves and packaged particles — interact with everything else in the Universe.
I really dig this video put together by Brady Haran of Sixty Symbols, because it captures both the surprise associated with today's announcement (turns out, a lot of physicists thought the Higgs Boson would win, too) and does a good job of explaining what Haroche and Wineland do, and why it's important.
Quote of the day: "Have you tried to capture a single atom?"
So, the sky looks blue because of the particular gases in our atmosphere reflect and scatter the blue wavelengths of light from the Sun. Fair enough. But that leads directly to a second question that, I'm ashamed to say, I never really thought to ask — why doesn't the light from all the stars in the Universe reflect and scatter off our atmosphere, producing a blue sky, all the time?
This Minute Physics video provides a great explanation, which is grounded in both the timey-wimeyness of astrophysics and the limitations of our own human biology.
So, on The Ellen DeGeneres Show they have a thing called a "Dance Dare". The basic idea: Sneak up around somebody when they aren't looking and boogie down, just outside their peripheral vision. If you're caught, stop dancing. Play casual. Wander away.
Which brings us to this video.
Krister Shalm is a postdoc in the Institute for Quantum Computing at the University of Waterloo, Canada. He is also a swing dancer.
A couple of weeks ago, Stephen Hawking visited the University of Waterloo and Krister took the opportunity to do a Dance Dare on the esteemed physicist. The other Ellen Dance Dares are sort of club dance-y in nature, but Krister opted for a little jazz jig more fitting his personal skill set.
A group of MIT students decided to test the performance of different tinfoil beanies to see how various designs (the "classical," "fez" and "centurion") interacted with commonly used industrial radio applications. They found that all three designs actually amplified these
mind control rays radio waves, suggesting that the tinfoil hat meme might be a false-flag operation engineered to trick the wily and suspicious into making it easier to beam messages into their skulls.
Among a fringe community of paranoids, aluminum helmets serve as the protective measure of choice against invasive radio signals. We investigate the efficacy of three aluminum helmet designs on a sample group of four individuals. Using a $250,000 network analyser, we find that although on average all helmets attenuate invasive radio frequencies in either directions (either emanating from an outside source, or emanating from the cranium of the subject), certain frequencies are in fact greatly amplified. These amplified frequencies coincide with radio bands reserved for government use according to the Federal Communication Commission (FCC). Statistical evidence suggests the use of helmets may in fact enhance the government's invasive abilities. We speculate that the government may in fact have started the helmet craze for this reason.
... We evaluated the performance of three different helmet designs, commonly referred to as the Classical, the Fez, and the Centurion. These designs are portrayed in Figure 1. The helmets were made of Reynolds aluminium foil. As per best practices, all three designs were constructed with the double layering technique described elsewhere .
A radio-frequency test signal sweeping the ranges from 10 Khz to 3 Ghz was generated using an omnidirectional antenna attached to the Agilent 8714ET's signal generator.