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Flip Book Physics

Out of print but sometimes available here:

From Amazon: BUY NOW: Flip Book Fan

Flip Book Physics: silly but clever, when one riffles through this flip book it does indeed create enough breeze to extinguish a candle, fitting to an animation of a fan- if a pun were a book! The psychophysics of flip books- when the image flash rate is above the flicker fusion frequency (approximately 16Hz) we perceive fluid motion- the basis for all movies and TV.

Triple Pendulum Chaotic Fidget 

Get this chaotic fidget spinner here:

From Amazon: BUY NOW: Triple Pendulum Spinner

Triple Pendulum Chaotic Fidget: This interesting spinner is made from stainless steel and features three physical pendulums each mounted with their own low friction bearing. In slow motion one can see the kinetic energy and angular momentum is transferred from one pendulum to another as the entire device rotates, with some spinning rapidly and others rotationally at rest- the intricacies chaotic motion, characterized by extreme sensitivity to initial starting conditions, tiny differences in how the system is released leads to dramatically different outcomes each time.

Spinnobi Springy Spinner 

Get one here! 

From Amazon: BUY NOW: Spinnobi Spinner

Spinnobi: a spinner with bounce! With springs mounted along the axis on both sides of the dense rotating silicone disk, this spinner demonstrates gyroscopic stability- keeping its orientation as it falls and bounces. Conservation of angular momentum on display with this new take on the spinner.

Disk Tesla Coil

Create amazing Telsa coil lighning at an affordable price! Please be sure to employ all appropriate safety precautions when utilizing any electrical circuity.  

From engineDIY: BUY NOW: Disk Tesla Coil

Click here for similar amazing devices from engineDIY

Disk Tesla Coil: incredible coronal brush discharges form intricate miniature lightning in this variation of the famous air core double-tuned resonate transformer invented by Nikola Tesla in 1891. In this novel design the coil is created using modern printed circuit board (PCB) technology producing a spiral of many conductive windings, so thin and close together it looks a bit like a gold phonograph record. The 10 cm long sparks are made possible by a very high voltage, but also a very fast discharge of a capacitor, and each lightning flash is accompanied by a dramatic popping sound characteristic of capacitor discharge (shown up close in 240fps slow motion). Powered by a 24V DC supply, this unit is fairly safe due to a low current (mA)- the discharge feels like a light tickle (but don’t touch the electrode- it gets hot). 

Hero's Engine

This live steam engine is available here:

From EngineDIY: BUY NOW: Hero's Engine

Hero’s Engine: the very first steam engine ever devised, the Aeolipile is a radial steam jet reaction turbine, an a invention attributed to Hero of Alexandria in the year 1 AD. Water within the spherical container is heated to produce steam which exits through nozzles directed at right angles to the radial direction, and by Newton’s third law these jets produce a torque about the rotation axis. There is no historical record of this engine being put to practical use in ancient times- except perhaps as the world’s first physics toy!

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.

Meteorite with CAIs

CV3 type carbonaceous chondrite with extremely old CAIs, cut and polished pieces can be found here: 

From eBay: BUY NOW: Meteorite with CAIs

Wikipedia has the details on the age of these very ancient minerals: CAIs

Meteorite with CAIs: oldest known solid material in our solar system- the white substance in this meteorite is called Calcium Aluminum rich inclusions (CAIs) and radiometric dating sets the formation time at 4.5673 billion years ago- a few million years older than the rest of the meteorite material and thought to be the first solid compounds formed in the protoplanetary disk before the planets even existed. This substance is most common in carbonaceous chondrites type CV3 as found in this 8 gram sample which was cut and polished on one side. This particular sample was found in 2012 in Northwest Africa. Only the molecules and atoms themselves are older than this CAI material! 


Get a similar affordable Zoetrope from these sources:

From Etsy: BUY NOW: Zoetrope 

From Amazon: BUY NOW: Zoetrope 

Zoetrope: the physics and psychophysics of motion animation- still images flashed in rapid succession produces the illusion of motion through persistence of vision. The slits are crucial to creating the illusion by blacking out the visual stimulus for a short duration- without these pauses only a blur is perceived. When the image flash rate is above the flicker fusion frequency (approximately 16Hz) we perceive fluid motion- the basis for all movies and TV. 

Feel Flux Loop

Available as a set, or individually (all come with the super powerful sphere magnet) here:

From BUY NOW: Copper + Aluminum Feel Flux

Get some magnetic viewing film here: 
From Educational Innovations: BUY NOW Magnetic Viewing Film 
From Amazon: BUY NOW Magnetic Viewing Film 

Feel Flux Loop: original (copper) and the "Skill Flux" version (aluminum)- toys that use Lenz's Law to manipulate a very strong neodymium magnet. A changing magnetic field (such as that from a falling magnet) induces an electric current in the copper, which in turn produce an electromagnetic field (but of lesser strength) with opposing polarity. Interestingly the magnet falls a bit faster through the aluminum even though the walls are thicker- Al is only about 60% as conductive as Cu- so it takes more material to induce the needed magnetic field using aluminum. Interestingly the Al tube is about half the mass of the Cu one, even though it is larger in volume. Swipe to see the effect via magneview film which allows a visualization of the magnetic field- note that the field extends and is visible right through the thick copper.

Switch Pitch Ball

Get one here: 

From Edicational Innovations: BUY NOW: Switch Pitch Ball

Switch Pitch Ball: this spherical assembly changes color by turning inside out when tossed into the air. A favorite of my mechanical toys with surprising physics. Interestingly the advertisements for this toy incorrectly claim air drag is involved in the transformation. To understand why the ball inverts first note that the ball is made of multiple components hinged together. In launching the ball from the hand an upward acceleration results in a torque that pivots each component around its center of mass, causing the rotation of these components in an organized way leading to the transformation. Imagine tossing a stick straight up. If the stick is perfectly vertical upon launch it will move straight up- but if it is initially slanted at all it will also begin to rotate upon launch. Similar physics underlies the motion of each component of the ball- shown here in 240 fps slow motion. The Switch Pitch is produced by the makers of the Hoberman Sphere. 

Golden Ferrofluid

Available on Etsy: BUY NOW Gold Ferrofluid Cell 

Golden Ferrofluid: colloidal ferromagnetic liquid in a specially prepared water-alcohol suspension. Curious behavior results from the interplay between magnetic force and surface tension. I'm still investigating the gold coloring and the specific makeup of the clear suspension fluid- both trade secrets it seems. The gold color appears to be a thin coating at the boundary between the ferrofluid and the suspension liquid.

Chaotic Fidget

This is the exact one used in the video- works well! 
From Amazon: BUY NOW Double Pendulum Chaotic Fidget 

Chaotic Fidget: a double pendulum spinner- chaos in the palm of your hand! This miniature double pendulum is made from stainless steel, which provides high mass so one can feel the unbalanced center of gravity shift about, and bearings in the joints allow for smooth and sustained motion. Slow motion reveals the intricacies of the chaotic motion, characterized by extreme sensitivity to initial starting conditions, tiny differences in how the system is released leads to dramatically different outcomes each time. 

Tesla Coil

For the price, this is the best one on the market I think and beautiful to look at in copper- the music function does not do much, but it is a great little Tesla coil and it comes with three accessories for the top. Please be sure to employ all appropriate safety precautions when utilizing any electrical circuity! 

From engineDIY: BUY NOW: Mini Tesla Coil

Tesla Coil: miniature low current version of the famous air core double-tuned resonate transformer invented by Nikola Tesla in 1891. The thick copper of the primary coil is set into three windings around the many windings of the tall secondary coil. This one uses a modern transistor circuit to excite the radio frequency oscillations that produce a voltage in excess of 50kV in the form of pulses that cycle about 100k times a second. This version is fed by a 24V DC power supply and is fairly safe due to a low current (mA)- but the circuitry does get hot and demands a huge heat sink with fan (the metal base can burn skin when operating). The coils comes with attachments- the spike produces a purple corona discharge as the voltage exceeds the breakdown voltage of air with current flowing into the air or arcing over to a grounded piece of metal. The corona discharge imparts momenta, and here the ends of a bent wire are set into rotation from the slight push of the escaping electrons. Swipe to see the ejected electron stream propel the end of a thin wire into a final state circular orbit. The more interesting behavior occurs during the initial transient orbits which seem to be hypotrochoid type curves beautifully captured here using the Slow Shutter app. 

Stomachion Puzzle

Get this 3-color laser cut acrylic version here:
From Kadon Enterprises: BUY NOW: Stomachion Puzzle

Also a very nice multicolor acyrlic version here:
From Etsy: BUY NOW: Stomachion Puzzle

Learn about the 1998 discovery of the lost writings of Archimedes (and the technology used to recover them) in this TED talk

Ancient Stomachion Puzzle: the oldest known puzzle, discovered in the writings of the great Greek physicist and mathematician Archimedes from some 2200 years ago. The puzzle is a dissection of a square into 14 polygons, where the areas of each piece are integer multiples of each other (a curious way to slice it up). In 2003 Bill Cutler showed that there are 536 district ways to configure these pieces to make the square (five are shown here), ignoring simple rotations and reflections. Swipe to see the most famous solution, attributed to Archimedes himself, that was found in an ancient manuscript discovered only in 1998- before this date historians knew the name of the puzzle, but no one knew what it looked like. Kate Jones, the maker of this particularly aesthetic version, found that when using only three colors for the polygons, there are only 6 solutions where no two pieces of the same color touch (four solutions shown here).


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.

Heart Gears

Get a nice 3D print made here:
From Etsy: BUY NOW: Heart Gears

Or print it yourself:
From Thingverse: Download Free: Heart Gears Print Files

Heart Gears: This 3D print is guaranteed to put your heart in a twist- comprised of eight bevel gears attached to an octahedron center block, with the axis of each gear oriented to the center of each face of the octahedron. Rotate any one gear 360 degrees and the heart shape will reform. Another amazing design by Emmett Lalish, first printed in 2014.