Just another blog on physics and for me to share my findings
"The pressure variations due to the sound waves affect the flow rate of flammable gas from the holes in the Pyro Board and therefore affect the height and colour of flames. This is interesting for visualizing standing wave patterns and simply awesome to watch when put to music."
Skip to 3:38 in the youtube clip to hear it with the music. The lo-fi track used to demonstrate is sick, and makes it that much more amazing to watch.
Veritasium’s new video has an awesome demonstration featuring acoustics, standing waves, and combustion. It’s a two-dimensional take on the classic Rubens’ tube concept in which flammable gas is introduced into a chamber with a series of holes drilled across the top. Igniting the gas produces an array of flames, which is not especially interesting in itself, until a sound is added. When a note is played in the tube, the gas inside vibrates and, with the right geometry and frequency, can resonate, forming standing waves. The motion of the gas and the shape of the acoustic waves is visible in the flames. Extended into two-dimensions, this creates some very cool effects. (Video credit: Veritasium; via Ryan A.; submitted by jshoer)
walter lewin did something like that too
NPR’s Skunk Bear Tumblr has a great new video on the schlieren visualization technique. The schlieren optical set-up is relatively simple but very powerful, as shown in the video. The technique is sensitive to variations in the refractive index of air; this bends light passing through the test area so that changes in fluid density appear as light and dark regions in the final image. Since air’s density changes with temperature and with compressibility, the technique gets used extensively to visualize buoyancy-driven flows and supersonic flows. Since sound waves are compression waves which change the air’s density as they travel, schlieren can capture them, too. (Video credit: A. Cole/NPR’s Skunk Bear)
When light travels through areas of different air density, it bends. You’ve probably noticed the way distant pavement seems to shimmer on a hot day, or the way stars appear to twinkle. You’re seeing light that has been distorted as it passes through varying air densities, which are in turn created by varying temperatures and pressures.
Schlieren Flow Visualization can be used to visually capture these changes in density: the rising heat from a candle, the turbulence around an airplane wing, the plume of a sneeze … even sound. Special thanks to Mike Hargather, a professor of mechanical engineering at New Mexico Tech, who kindly provided a lot of these videos.
I’m totally Schlieren right now. Amazing sights of sounds.
Want to know which elementary particle best describes you? Well this interactive quiz by the DESY research centre and Universum Bremen will show you based on how you see yourself.
* My top 3 particles were the gluon, tau neutrino, and up quark.
From the hand of Andrew Pontzen (@apontzen) and Tom Whyntie (@twhyntie) TED Ed bring us a divulgative introduction (the first in a series) about ‘The Fundamentals of Space-Time’. Very basic but pretty funny. Animation by Giant Animation Studios.