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Two Marble Puzzle

Another version of this puzzle available here: 
From Etsy: BUY NOW Two Marble Puzzle 

From Amazon: BUY NOW: Two Marble Puzzle, or get this set of puzzles

Two Marble Puzzle: physics brain teaser- move both marbles to their top locations on each side simultaneously. The solution to this puzzle relies on some fun basic physics principles- can you figure out which ones? Swipe to reveal solution. Found this well made version of this classic physics puzzle at a gift shop in San Francisco (note Golden Gate Bridge motif).

Tension Suspension: Tensegrity Scuplture

I made this device from these components:

From Amazon: BUY NOW:  heavy guage copper wire (for frame), inexpensive necklace chain (for connections), and hobby wire (to fasten chain to copper frames).

Check out these other Tensegity toys I've posted. 

Tension Suspension: an interesting take on tensegrity where one heavy wire frame seems mysteriously suspended above another. This sculpture features strings (chains used here to make it look more dramatic) in tension equilibrium, with the top wire frame hanging from the bottom frame by the strand in the center, and the other three strands in tension to keep it from tipping over. This configuration is related to the concept of tensegrity invented by Kenneth Snelson and made famous by the architect Buckminster Fuller in 1949.


Coin Escape Puzzle

Available here: 
From eBay: BUY NOW: Coin Escape Puzzle 

From Amazon: BUY NOW: Coin Escape Puzzle

Another coin escape puzzle (fits US Dollar), the YOT: 
From Amazon: BUY NOW 
Silver Dollar Escape Puzzle

Coin Escape Puzzle: physics brain teaser- remove the coin without breaking the container or using any tools other than your hands. Of course you spin it to get the quarter out- but exactly how? The solution to this puzzle (like others featured here) relies on some fun basic physics of spinning things. Answer below and swipe to reveal solution. 

Pentakis Geometric Kaleidoscope

This item is hard to find, but I believe it is in stock here: 
From AHA in Zurich: BUY NOW Pentakis 

for More kaleidoscopes click here

Pentakis Geometric Kaleidoscope: three triangle mirrors in a pyramid configuration create a stellated dodecahedron. The tapered mirrors are in the form of a 60°-72°-60° isosceles triangle with the apex of the pyramid cut off just right to form the triangle of light that is then reflected up to 60 times to create the star in the center of view. Pentakis by Caspar Schwabe. 


Reuleaux Rotor

This toy is availble from Amazon Japan and will ship to the US:

From Amazon.jp: BUY NOW: Reuleaux Rotor Wodden Toy

Reuleaux Rotor: this famous curve of constant width, the Reuleaux triangle, can rotate such that at all times it remains in contact with all four sides of a square. As demonstrated by this wooden toy from Japan, the rotor covers approximately 98.77% of the area of the square, missing only the sharp corners. The curves in the corners are in the shape of an elliptical arc. Fun fact: a Reuleaux triangle has a perimeter equal to pi times its width- just like a circle! 

Spherical Dice

A must for any die/dice collectors: 
From Amazon: BUY NOW Spherical Dice 

Click this link for other amazing dice featured on @physicsfun 

Spherical Dice: these fair six "sided" dice are hollow inside with a ball that weights each sphere such that one of the six values is always on top. When these dice are rolled (literally!) the internal weight lands in one of six cavities inside creating a low center of mass which aligns one of the numbers to the top. Another low center of mass toy! 

EDC Gyroscope

Precision machined stainless steel gyroscopic spinners avaialbe here:

From mechforce.com: BUY NOW: EDC Gyroscope

EDC Gyroscope: a metal rotator spins freely within a gimbal arrangement and features precision bearings used throughout (1 ball bearing in core plus 4 micro-bearings in the intermediate ring). Spin up the center gyro and conservation of angular momentum will keep its axis of rotation pointing in a constant direction even as the outer rings are rotated to and fro. Precision machined from stainless steel- the ultimate spinner!


SpinForce Globe

This fun toy available here: 

From eBay: BUY NOW: SpinForce Globe with Cars
From Amazon: BUY NOW 
SpinForce Globe with Two Cars 

SpinForce Globe: entering through trap doors two spring powered toy cars hug to the inside of the acrylic sphere. Given sufficient velocity, the surface normal force supplies the centripetal acceleration that keeps the cars in their gravity defying trajectories. The kinetic energy is supplied by a pullback motor- a clutching mechanism patented in 1952 found in many toys, where pulling the toy car backwards winds a coil spring. A toy full of physics!

Kinetic Traced Hyperboloid

This hard to find sculpture curretnly available here:

From Amazon: Hyperbolic Kinetic Sculpture

Kinetic Traced Hyperboloid: a straight rod glides through a symmetric pair of curved holes in this kinetic sculpture based on the hyperboloid, the 3D ruled surface traced by an offset revolved straight line. This version is made of anodized aluminum and rotates via gearing and a motor powered by two AA batteries in the base. 

Earth Mass Black Hole with Space Warping Display Stand

Precision machined tungsten alloy spheres avaulable here:

From STEMCell Science: ORDER NOW: Tungsten Black Hole Replica

Earth Mass Black Hole: this sphere of tungsten alloy has a diameter of 17.7mm, a precision representation of the size of the event horizon of a black hole with a mass equal to that of the Earth! If the entire mass of the earth could somehow be compressed to the size of this sphere, it would indeed collapse to a black hole with an event horizon defined by a Schwarzschild radius of 8.87mm. For comparison a black hole with the mass of the sun would be 6km across. This black hole replica is made of one of the densest materials available, a tungsten alloy with ?=18.5 g/cm³ which produces a strange sensation when you hold it, with a weight of twice that of a ball bearing of equal size.


Nixie Tube

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. 

Vortex Dome

Get one from David Fowler's Etsy shop: 
From PhysicsHack: BUY NOW: Vortex Dome Kalliroscope 
Made with extraordinary craftsmanship and high quality materials, and sold at a very reasonable price! 

Vortex Dome Kalliroscope: kinetic art with rheoscopic fluid in a rotating base. Visualizing the invisible- the Vortex Dome is the creation of engineer/inventor and @physicsfun featured artist David Fowler aka @physicshack who creates this modern rotating kalliroscope that generates complex and beautiful structures similar to those seen in the cloud bands of the gas giants of our solar system like Jupiter. The capsule is constructed of high quality glass on a heavy stainless steel base which glides on bearings for long spin times. 


Spinning Liquid Paperweight

Many versions available here 
From Amazon: BUY NOW Liquid Wave Paperweight Toy 

Spinning Liquid Paperweight: two immiscible liquids (three if you count the air bubble) are sorted under gravity by density with the densest on the bottom and the lightest on top. If 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, symmetric waves travel and reflect along the curved surface for the first few rotations until damped out via viscosity and friction. The plastic fish have a density between that of the two liquids so they stay at the boundary layer. 

Tail Spin Geared Kinetic Toy

Get one here: 
From eBay: BUY NOW: Tail Spin Kinetic Toy

Tail Spin Geared Kinetic Toy: fourteen gears arranged on seven linked segments meshed in such a way that the configuration can roll up and stack compactly or extend into a line. With a flick of the wrist, one can impart enough angular momentum to the assembly to cycle it through its full range of motion- shown also in 240fps slow motion at the end of the video. Invented by Oskar van Deventer and produced by Think Fun toys.