Recent Posts

Perpetual Motion Simulator V2.0

This new demonstration transparent model is available here:
From Amazon: BUY NOW: Transparent Perpetual Simulator

Get the original here:
From Etsy: BUY NOW: Perpetual Marble Machine (reccomended seller: William Le of BackToNatureDecor)

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Perpetual Motion Simulator V2.0: a version with a transparent casing that reveals the sophisticated mechanism and electronics behind the newest “perpetual motion” toy that hit the internet a couple years ago. The original version was expertly crafted to make the base look like a block of wood (see post from November), but here we see a battery, a coil, a set of large capacitors, and a blue sensor unit along with circuit boards. The sensor detects the descending metal ball and then in an amazingly short amount of time the circuit discharges the capacitors through the coil to produce a magnetic pulse that accelerates the ball. Still looking into what kind of sensor is used- but this circuit is an excellent reminder that when someone claims a perpetual motion device the question to ask is “where’s the battery hidden?”

See Steve Mould's excellent video for details on the Perpetual Motion Simulator Circuirtry 

Chaotic Double Pendulum with Ring

Availalble here:

From Grand Illusions Ltd.: BUY NOW: Chaotic Pendulum Kit

Note: this site contains affiliate links for which I may be compensated

Chaotic Double Pendulum with Ring: 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 back and forth between the potential energy of gravity to the kinetic energy of motion. Chaotic 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. Another extraordinary design by Kontax Engineering Ltd.

UFO Mirascope

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

Alien version available here

Note: this site contains affiliate links for which I may be compensated

UFO Mirascope: two parabolic mirrors create a 3D image above the actual object. The image of the tiny alien made here is not a hologram and is produced solely by reflection of light rays between special concave mirrors. Love the space saucer theme on this version. The mirascope design principle was discovered circa 1969 by Landry and Elings at UC Santa Barbara.

Hyperbolic Holes

This inexpensive kit available here:

From Amazon: BUY NOW: Hyperbolic Holes Kit

Note: this site contains affiliate links for which I may be compensated

Hyperbolic Holes: a straight rod, in this case a pencil, glides through a symmetrical pair of curved holes. The design is based on the hyperboloid, the 3D ruled surface traced by an offset rotating diagonal line. This device is sold as an inexpensive kit to assemble yourself, and includes a motor with geared drive and pre-cut pieces. The pencil is my addition- sharpened to just the right size to clear the curved openings.

Simple Stirling Engine

Get this amazing model engine here:

From EngineDIY: BUY NOW: Simple Stilring Engine

See other featured DYI devices here: EngineDIY Models

Note: this site contains affiliate links for which I may be compensated

Simple Stirling Engine: Perhaps the simplest piston engine ever devised- a single piston powered by a tiny alcohol lamp. Glass components allow a view of the internal workings of this design, and the interesting startup behavior from oscillation to full rotation. Heat engines produce mechanical motion from a difference in temperature- here the piston side is near room temperature (the central aluminum post is an excellent conductor and acts as a heat sink as the gas flows through), and the test tube is kept at high temperature via the flame, with metal fibers to help conduct the heat into the air (this component is called the regenerator). Swipe to see the elegant assembly of this model, and swipe again to see the engine power down. This external combustion design is attributed to Scottish engineer Robert Stirling back in 1816.

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

See my other posts on the Feel Flux devices

Note: this site contains affiliate links for which I may be compensated

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.

Klein Bottle

Get this mathematical glass art here:

From Etsy: BUY NOW: Klein Bottle

Note: this site contains affiliate links for which I may be compensated

Wikipedia has great details on the Klein Bottle

Klein Bottle: 3D representation of a four dimensional mathematical object with one side, no edges, and zero volume. Kind of like a MoĢˆbius strip with no edges.* Math meets glass art with this fun “lamp shaped” version! *only achievable in 4D space 

Trisected Sphere Puzzle

Get one here (color of your choice):

From Etsy: BUY NOW: Trisected Sphere Puzzle

Note: this site contains affiliate links for which I may be compensated

Trisected Sphere Puzzle: three identical pieces interlock to form a ball in this elegant 3D printed dissection puzzle. The sphere is sliced following a helical path from one pole to the opposite pole, creating a smooth disassembly and reassembly.

See other fun geometric puzzles here: dissection puzzles

Galton Board with Pascal's Triangle

Get this amazing Galton Board probabutly demonstrator here: 

From Amazon: BUY NOW: Galton Board (comes with an wonderful fact filled booklet). 

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Galton Board with Pascal’s Triangle: 6000 steel balls (and one gold bead) fall through 14 levels of branching paths and always end up matching a bell curve distribution. Each ball has a 50/50 chance of going left or right at each branch such that the balls are distributed at the bottom by the mathematical binomial distribution. In addition the number of balls in each bin can be predicted by Pascal’s triangle, where the number on each hexagonal branch point represents the number of possible paths to reach that point from the top. See if your eyes can follow the path of the gold bead (representing a single random path) in the 240fps slow motion segment of the video. This extraordinary design by Philip Poissant is a modern version of the Galton Board, invented by Sir Francis Galton(1894) to demonstrate the Central Limit Theorem and show how random processes gather around the mean. Made and distributed by Four Pines Publishing Inc. and 

Chiral Aperiodic Monotile Puzzle

Get this amazing puzzle set here:
From Etsy: BUY NOW: Specter Tile Set by Nervous Syestem

Note: this site contains affiliate links for which I may be compensated

Read the published paper: A chiral aperiodic monotile

Chiral Aperiodic Monotile: these puzzle pieces are all identical in shape, based on special family of forms called “specters”, and are key to a major mathematical discovery in May of 2023. Specters will tessellate a plane to infinity, similar to how squares or hexagons can tile out with no gaps. However specters are identically shaped tiles which fill the plane aperiodically- if one tries to shift a part of a specter tiling, the shifted part will not align or match up with any other part of the same tiling- all the way out to infinity! The fact that aperiodic tessellations exist at all is pretty amazing, and Sir Roger Penrose (Nobel prize in physics 2020) is also famous for discovering a pair of regularly shaped polygons in the 1970s that tile in this aperiodic way. Specters were discovered by the same team of mathematicians (Smith, Myers, Kaplan, and Goodman-Strauss) who discovered “the hat” aperiodic monotile in March 2023, but the hat needs its mirror image to complete the tiling whereas the specter does not. An amazing development found only two months after the initial major breakthrough. Credit to the @nervous.system design team for modifying the specter into an interlocking puzzle piece form- and assembling these without gaps is a fair challenge! 

Levitating Mini Moon Lamp

Get this fun lamp here (comes with both Mini-Moon and silver sphere magnet):

From Amazon: BUY NOW: Levitation Lamp

Note: this site contains affiliate links for which I may be compensated

Levitating Mini Moon Lamp: tapping the floating illuminated Moon turns this LED lamp off and on in this strange design. The Moon with embedded magnet floats a couple centimeters from the surface of the base when plugged in, and feels springy to the touch. Within the base is a control system with adjustable electromagnet coils in a feedback loop with Hall effect sensors which allow for fine tuning of a magnetic field to precisely balance the pull of gravity on the tiny Moon.

Repelling Marbles Puzzle

Get this affordable and fun kit here:

From Educational Innovations: BUY NOW Mystery Marbles Puzzle Kit 

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Mystery Marbles Puzzle: a physics brain teaser (now available as a kit) what's going on here? Three glass marbles can move but stay separated in this liquid filled tube no matter the orientation- why do they not touch? Swipe for reveal of components. 

See also: Poly-acrylamide Polymer Vanishing Act

Tree & Mushroom Top Set

From Art of Play: BUY NOW: Woodland Top Set

See other flip over tops here: Tippe-Tops

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Tree and Mushroom Top Set: a whimsical woodland scene with two surprises- a flip-over tippe-top (mushroom) and a conical Tree shaped top that is more stable spinning on its trunk than its top. This set is made in Austria and comes with a branch wood stand.


Dandelin Spheres

I found this beautiful model on eBay and I'm not sure of its age or origin. 

Grant Sanderson describes the elegant geometry behind this curious arrangement. 
On YouTube: 3Blue1Brown descibes the Dandelin Spheres  

Wikipedia also has a good description: the Dandelin Spheres

Here are some 3D print models of conic sections:
From Etsy: BUY NOW: Conic Section Models

Note: this site contains affiliate links for which I may be compensated

Dandelin Spheres: Slicing a cone with a plane can produce an ellipse, and two spheres encapsulated by the same cone will always have the small sphere touching one focus and the large sphere contacting the plane at the other focus. This beautiful acrylic model shows this geometry for one choice of cone width and dissecting plane angle- but it always true. This geometric construction is named for its inventor, French mathematician Germinal Pierre Dandelin back in 1822, and with it he proved theorems concerning properties of ellipses and other conic sections- mathematical entities that play a roll in much physics- including the orbits of planets. Fun math that I wish someone would have showed me back in high school!

Spinning Liquid Pen

Get this pen set here (dolphin, turtle, polar bear, penguin):

From Amazon: BUY NOW: Spinning Liquid Motion Pens

Note: this site contains affiliate links for which I may be compensated

Spinning Liquid Pen: two immiscible fluids (three if you count the air bubble) are sorted under gravity by density with the densest on the bottom and the lightest on top. When the container is rotated, the boundary between the layers forms a parabola due to the added influence of centripetal acceleration as seen here in 240 fps slow motion. The plastic dolphin has a density between that of the two liquids so it stays at the boundary layer. A rather silly toy- but so much physics to explore here! 

Motion of Rolling Sphericons

Get these and other amazing developable rollers here:

From Etsy: BUY NOW: Hexacon and Sphericon Rollers

Note: this site contains affiliate links for which I may be compensated

Sphericons are unique solids that roll in such a way that every point on their surface comes in contact with the plane. Solids from the sphericon family all have one side and two edges. Each sphericon is based on an even sided regular polygon, with the basic sphericon derived from a square, and the next two possible shapes are the hexa-sphericon and octo-sphericon, each rolling with a more complicated path.