Demonstrating refractive index
[I]f the refractive index of two materials is the same, as is the case for sunflower oil and Pyrex, then light doesn’t bend at all, and you end up with the nice effect demonstrated [in the video]
Monthly Archives: September 2012
Refurbishing the Light Bulb
Kickstarter: LIFX: The Light Bulb Reinvented
LIFX is a WiFi enabled, multi-color, energy efficient LED light bulb that you control with your iPhone or Android.
This looks cool. Remote control of your lights, adjust colors, have them automatically turn on/off when you arrive/leave (if you take your phone with you; I’m assuming this is tied to the phone’s location sensing)
No Bones About It
Skeleton light sculptures
Throw Her Into the Pond!
If sodium weighs the same as a duck …
…Even Though The Sound of it is Something Quite Atrocious
More superhydrophobic fun
Superhydrophobic Coating Allows Boiling Water without the Creation of Bubbles
Water can be made to boil without any bubbling if a boiling surface is specifically treated so that the vapor cushion does not break down. This is linked to the Leidenfrost effect.
Here Be Dragons
Being a map of physics, containing a brief historical outline of the subject as will be of interest to physicists, students, laymen at large; Also giving a description of the land of physics as seen by the daring sould who venture there; And more particularly the location of villages (named after pioneer physicists) as found by the many rivers; Also the date of founding of each village; As well as the date of its extinction; and finally a collection of various and sundry symbols frequently met with on the trip.
Large version of the map, from The Quantum Pontiff blog.
Straight Though the Heart
There’s nothing physically blocking the atoms from flying right through the channel– in fact, an atom that enters the channel will always exit the other side without slowing down along the way. This is termed “ballistic,” a term that will always have a special place in my heart thanks to an incident at my Ph.D. defense.
After This We Hypnotize the Drops
Acoustic Levitation of Liquids Looks Like Magic
No magic show: Real-world levitation to inspire better pharmaceuticals
The acoustic levitator uses two small speakers to generate sound waves at frequencies slightly above the audible range – roughly 22 kilohertz. When the top and bottom speakers are precisely aligned, they create two sets of sound waves that perfectly interfere with each other, setting up a phenomenon known as a standing wave.
The speed of sound is about 340 m/s, so a 22 kHz wave has a wavelength of about 1.5 cm; the nodes would thus be half that distance apart, but you wouldn’t have to fill every node. Notice the effect at 0:30, where the standing wave is adjusted — you can see the drops move up and down, in tandem.
This seems to be analogous to a dipole force trap in atomic physics. If that’s so, you’d have a radial pressure gradient also giving confinement, which might account for the somewhat strange look to the speakers.
A Robot Called Horse
This video depicts field testing of the DARPA Legged Squad Support System (LS3). The goal of the LS3 program is to demonstrate that a legged robot can unburden dismounted squad members by carrying their gear, autonomously following them through rugged terrain, and interpreting verbal and visual commands.
How Does it Do in the Rain?
This $9 Cardboard Bike Can Support Riders Up To 485lbs
Engineers told Gafni that his idea was impossible. Yet he realized that paper could be strong if treated properly. As in crafting origami and tearing telephone books, he explains, “[if] you fold it once, and it’s not just twice the strength, it’s three times the strength.”