More than 500,000 Brazilian free-tailed bats, emerging to forage at night, light up the pitch black darkness of New Mexicos Carlsbad Cavern in this thermal infrared video.
Category Archives: Physics
"V" is for Vortex
Flying in the shape of a “v” allows geese to have an equal field of vision while conserving energy, using wingtip vortices to decrease any drag in flight. The bird in the front is working the hardest, but when the leader grows weary it rotates to a position farther back and allows another feathered pilot to take its place.
Much like cycling teams. (except for the feather part) … (usually)
Obligatory joke:
Q: Do you know why the “V” is usually longer on one side than the other?
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Recipe Substitution
If you have no cat, use a virus instead. probably not said by Erwin Schrödinger
Schrödinger’s intention was to illuminate the paradoxes of the quantum world. But superposition (the existence of a thing in two or more quantum states simultaneously) is real and is, for example, the basis of quantum computing. A pair of researchers at the Max Planck Institute for Quantum Optics in Garching, Germany, now propose to do what Schrödinger could not, and put a living organism into a state of quantum superposition.
Note that they are not attempting to put the virus in an alive/dead superposition.
Snap, snap, grin, grin, wink, wink.
Say no more.
Gedanken
Morning Coffee Physics: The Physicist’s Toolbox: Thought Experiments
Physics is an empirical science which means that you can do all the thinking and theorising you want, but at the end of the day, if it doesn’t match the real world experimental results, it’s wrong.
I’ve harped on this before. If you manage an unphysical result or contradiction in your thought experiment, it means your thought is wrong.
See also The Physicist’s Toolbox: Symmetry
Bridling the Breeze
The Boy Who Harnessed the Wind: Persistence, Jury-Rigging, and Ingenuity Against All Odds
A Malawian youth, whose family could not afford his school tuition, learns some physics and builds a windmill to generate electricity for his village.
William scoured trash bins and junkyards for materials he could use to build his windmill. With only a couple of wrenches at his disposal, and unable to afford even nuts and bolts, he collected things that most people would consider garbage-slime-clogged plastic pipes, a broken bicycle, a discarded tractor fan-and assembled them into a wind-powered dynamo. For a soldering iron, he used a stiff piece of wire heated in a fire. A bent bicycle spoke served as a size adapter for his wrenches.
Urine Trouble Now
sciencegeekgirl: If a boy pees on the floor and there’s nobody there to see it
The boys’ urinals were often surrounded by a puddle of “liquid.” Were the urinals weeping water? Or were the boys purposely urinating on the floor (as the janitor believed)? And, most importantly, how can we use our good friend SCIENCE to solve this mystery, the teacher asked?
Is there a powder I can sprinkle on the floor that will turn a particular color?
A UV light to shine on the puddles that will fluoresce?It turns out that, yes, there is such a device!
Note that I have not deigned to confirm this effect with my own UV light.
However, I had read about the etched fly “targeting system” discussed; I had charged a friend of my brother’s with the task of finding one of these when he was in Europe. I had read they had been installed in the Amsterdam airport, but he didn’t see any there. This was taken at a restaurant in Berlin
The Nougat has Cleared the Tower
There’s a fairly well-known science question which asks
How does the amount of energy per gram of TNT compare with the energy per gram of a chocolate chip cookie?
I’ve discussed before why I think the answer should be, “About the same,” if you’re doing a first-order approximation, and depending on what options you give for an answer.
We’ve also visited the energy content of a candy bar. So along that vein (or clogged artery) we have
which tests sugar as an ingredient in rocket propellant, in the form of pixy sticks, creme from an oreo cookie, and a Snickers bar.
Creme filling from one Double Stuff Oreo weighed out at 5.7 grams. Mixed with 11.4 grams finely powdered KNO3 (FireFox) with mortar and pestle.
Result: Burns very sluggishly, requires some assistance from torch flame
Adjustment: Added 0.2 grams red iron oxide (Fe2O3) to catalyze the burn. Works much better.
Great Power
It also comes with great current times potential difference.
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As Long as it's not Taylor-Theismann
Rhett analyzes a football collision. Momentum and Football