Recent Posts

Poly Density Puzzle

Get the kit here: 
From Educational Innovations: BUY NOW Polydensity Bottle Kit 

Folow the link above for details of the physics explanation. 

Poly Density Puzzle: my favorite science brain teaser- white beads and blue beads "float" oddly separated beneath the surface of a clear liquid. If the contents are mixed by shaking the container, the white beads gather at the top and the blue sink to bottom! Adding to the mystery; after about 30 seconds the two layers of beads will have slowly moved back to the middle. What is your guess as to the physics behind this behavior?

Mini Double Pendulum

Get this precision machined and balanced desk pendulum here: 
From Etsy: BUY NOW Double Chaotic Pendulum 

Mini Double Pendulum: the intricate dance of chaotic motion from a simple assembly of two physical pendulums (one attached to the end of the other) with the energy of the system moving frenetically back and forth between the potential energy of gravity to the kinetic energy of motion. Chaotic motion (shown here in 240 fps slow motion) is characterized by extreme sensitivity to initial starting conditions, tiny differences in how the system is released leads to dramatically different outcomes each time. This well made precision bearing double pendulum is made by Doug Cvelbar.

Mirascope

Similar devices available here:
From Educational Innovations: BUY NOW Mirascope 
From Amazon: BUY NOW Mirascope 
 

Mirascope: two parabolic mirrors create a 3D image above the actual object. A repost of one of my favorite physics toys ever. The image of the dice made here is not a hologram and is produced solely by reflection of light rays between special concave mirrors. Discovered circa 1969 by Landry and Elings at UC Santa Barbara.


5 Shuttle Trammel of Archimedes

Get similar devices here: 

See/buy a 3-Shuttle version here: 
From Curiosity Box: 
Trammel of Archimedes

From Etsy: BUY NOW 
Trammel of Archimedes

From eBay: BUY NOW 
Trammel of Archimedes


See this great video by the Mathologer for more details: Secrets of the Nothing Grinder 

5 Shuttle Trammel of Archimedes: similar to yesterday’s post- but more math is revealed as extra shuttles are added. As the shuttles take turns completing their straight line journeys, the end of the crank arm traces an ellipse- and each of the five shuttle points define points on a smaller circle that rolls within the perimeter of the device. This version was crafted from fine maple, cherry, and oak by artisan Neal Olsen. 

Rolling Marble Sculpture

Similar and innovative rolling ball sculptures available here:

From Etsy: BUY NOW: 3D Printed Marble Runs

See more (miniture) marble runs here: Marble Run Fun

Rolling Marble Sculpture: marbles perform gymnastics as potential energy of gravity is converted to kinetic energy. An elegantly designed auger conveyor, an Archimedes' Screw, brings the marbles back to the top (powered by an AA battery and a small motor). Conservation of angular momentum produces a simulation of decaying orbits as the marbles whirl down the the main funnel shaped feature. 

Niji Cube

Find this cube and other rainbow making creations by this artist here:

From Etsy: BUY NOW: Niji Cubes

Niji Cube: a stunning kinetic art object constructed from acrylic and thin layers of plastic diffraction grating. Just add a white light source to produce an explosion of vivid colors with these creations by artist Minato Takeo. Here the rainbow spectrum is produced not by refraction like that of a prism, but instead by diffraction, where light waves deconstructively and constuctively interfere. A wonderful object to place on a sunny windowsill or, as in this video, to cast the beam of a flashlight through in a darkened room. 


Dot Animation Card

Five animations to choose from- collect them all!

From Art fo Play: BUY NOW: Dot Animation Cards

Dot Animation Cards: a unique version of barrier-grid (kinegram) animation where a matrix of holes allows only some of the dots on the covered card to show in succession producing the appearance of motion. In this clever design rotating the card with dots by 180 degrees reveals a second animation. Affordable kinetic art by Shigeki Naito that plays on the psychophysics of vision.

Aristotle's Wheel Paradox 

Get this demonstration puzzle here:

From Etsy: BUY NOW: Aristotle's Wheel

WIkipedia has some details on the Wheel "Paradox"

Aristotle’s Wheel “Paradox”: How does the smaller attached disk travel the same length as the larger one if both disks only make one full rotation? Note the shorter path of the smaller disk, if rolled on its own. This beautifully made demonstration depicts an issue of geometry and motion that perplexed the best minds of humanity for 2000 years. The ancients knew the formula for circumference, and C=2πR for the large disk is clearly greater than C=2πr for the smaller- so how could the smaller disk, rotated once, still travel the distance of the larger one if attached? The great Galileo even offered a solution to the problem in his book Two New Sciences, where he approximated the situation as concentric hexagons and considered the limit as the number of sides increased. So what is the best answer to make sense of this situation?

Floating Yen

These aluminium 1 Yen coins are the perfect denisty to float as shown in the video:

From Etsy: BUY NOW: 1-Yen Coins (20)

Floating Yen: the surface tension of water is strong enough to suspend the aluminum coin, and a trapped column of air in a second glass can submerge a portion of the surface with the coin. The 1-Yen coin has just the right mass and density for this demonstration. One of my favorite DIY physics demonstrations.


Magnetic Cube

Many colors to choose from: 
From MagneticCube.com: BUY NOW Magnetic Dice Cube 

See also the original indestructibles post: Magnetic Acrylic Rubik's Cube 

Magnetic Cube: a twisty Rubik’s Cube puzzle made from 27 dice and 108 neodymium magnets. This cube includes the scrambled states and solutions of the original 3x3 Rubik’s Cube but is held together only by magnets! The magnets, in this special configuration, lock the dice together with a satisfying click upon rotation. This beautiful cube was produced by Owen Lillywhite of magneticcube.com and is based on a gfixler design posted on instructables.

Celestial Sphere: the Stars of the Night Sky

Created by Clemens & Christoph of CinkS labs: Available in a cube too! 
From CinkS Labs: BUY NOW: Celestial Spheres

Celestial Sphere: the positions of 5068 stars as they appear in the night sky- along with 88 constellations, laser etched into a crystal sphere. This globe includes all stars of sixth magnitude or brighter- basically all the stars that the average and unaided human eye can see in the sky. The Milky Way in a Sphere: the distribution of stars in our home galaxy, laser etched into a crystal sphere, according to the most recent telescopic surveys and mappings- including the stars in the Sagittarius Dwarf Galaxy (a small galaxy that is simultaneously orbiting and getting absorbed into the Milky Way) and the major globular clusters outside the main disk

Fused Optical Fiber Image Conduit

Here are some similar image conduits- ones that magnify. These taper magnifiers are special application devices and are typically very expensive, but often some can be found on eBay: 
From eBay: BUY NOW: fiber optic plate

This PDF file by SCHOTT Glass industries has a great introduction to the physics and applications of this fiber optic technology, and the amazing process of how these image conduits are made: An Introduction to Fiber Optic Imaging - SCHOTT North America 

Fused Optical Fiber Image Conduit: this cylinder is made of one million fiber optic channels per square centimeter, each fiber providing one "pixel" of the transmitted image. Each fiber has a core of clear glass encased in a thin shell of glass with higher refractive index- but each is only 10 micrometers in diameter. This conduit contains over 6 million such fibers! With thanks to Mark Setteducati for supplying this specimen. 


Primed Siphon

Available here: 
From Shapeways: BUY NOW 
Primed Siphon Arch

Primed Siphon: liquid moves until the water levels are equal- curious combination of the effects of gravity, molecular cohesion, and atmospheric pressure. The tube is hollow and pre-filled with water, and the spherical shells on each end are cups also full of water. With each end of the tube submerged into each cup, atmospheric pressure holds the water in the tube until the siphon can be placed to connect the glasses. 

Pisces Kinetic Art Lamp

The Pisces Lamp is now avaialbel for purchase here:

BUY NOW: Pisces Kinetic Art Lamp

From the same artist who created the Aquarius Fountian Lamp

Pisces Kinetic Art Lamp: standing waves of a rotating string are illuminated by strobing light in this new kinetic sculpture by artist and computer engineer Stephen Co. With the help of programmable micro-controllers, strips of addressable RBG LEDs are made to flash in sequences that make the rotating string change colors, merge into spoon shaped surfaces, or split into multiple braids. The string is propelled by small motors and the standing waves can have multiple nodes, which can be altered by touching the string while in motion.

Magnetic Tensegrity Table

Available here:

From sphidget.com: BUY NOW: Magnetic Tensegrity Table

See similar scupltures here: Tensegrity on @physicsfun

Folow this link for Mova kinetic globes:  Mova Globes- Earth and Planets

Magnetic Tensegrity Table: This CNC machined tensegrity sculpture replaces the center tension member (chain) with a pair of attracting neodymium magnets. Made from 6061 aluminum and nickel plated steel chain, the “Impossible Table” is the creation of Kevin Sayers of sphidget.com. The table can support up to about a kilogram of mass, and makes for a nice display stand for my Mova globe of Pluto (swipe to view). Another fun configuration of the tensegrity concept, invented by Kenneth Snelson and made famous by the architect Buckminster Fuller in 1949. 


Magnetic Suspension Lamp

Available for under $100 US: 
From Amazon: BUY NOW 
Magnetic Suspension Lamp 

From eBay: BUY NOW 
Magnetic Suspension Lamp 

Magnetic Suspension Lamp: not only does this lamp defy gravity, the LEDs in the bulb are powered through wireless induction (no batteries needed). This kind of levitation uses a control system with an adjustable electromagnet in a feedback loop with Hall effect sensors which allows for fine tuning of the magnetic field to exactly balance the pull of gravity. If this lamp design is unplugged (or the power goes off) the bulb assembly does not fall, but instead snaps onto the upper armature via strong permanent magnets embedded within. Amazing physics demonstrated by clever engineering! 

Nixie Tubes and Clock

The Nixie Tube Clock in the video is of amazing craftsmanship- real hardwood with brass accents and solid construction. Get one from this excellent shop: 
From Etsy: BUY NOW 
Nixie Tube Clocks 

Nixie Tube: long before there were 7 segment LED displays there was the Nixie- cold cathode tubes with a wire mesh and 10 cathodes shaped in the form of numerals 0-9 that illuminate through neon glow discharge. The “Numeric Indicator eXperimental 1” or NIX 1 was introduced in 1955 by Burroughs Corporation and manufactured until the 1990s. This clock uses modern electronics to power Russian versions called the ИH-19A where the numbers are stacked so the front symbols obscure each lighted cathode minimally: from back to front 1320984756.