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Newton's Spindle

This unique toy only available here:

From safetynailer.com: BUY NOW: Newton's Spindle

Follow this link for a regular Newton's Yo-Yo

Newton's Spindle: the latest innovation- a quite clacker (lol!) which uses neodymium magnets as the swinging weights. The weights still collide but without making physical contact via magnetic repulsion, yet the exchange of momentum is just like that of a regular Newton’s yo-yo. Newton's 3rd Law states that action force equals opposite reaction force- here the red and blue weights (embedded magnets) are equal in mass, so the forces of each collision provide accelerations that are equal and opposite such that the deceleration of the incoming sphere is equal to the acceleration of the outgoing sphere and the spheres trade places leaving one always at rest.

Tensegrity for the Desk

Get this affordable physics tensegrity sculpture here:

From Etsy: BUY NOW: Tensegrity Sculpture

Tensegrity for the Desk: an elegant, and stackable, desk toy version of this popular tensegrity configuration by maker/designer Micah Murdoch. Constructed from poplar wood, the design assembles easily with clever ball and socket connectors at the ends of the nylon support lines (3 long, 1 short). Stacking them seems to only increase the illusion of floating with the subtle way these structures defy gravity. Another fun configuration of tensegrity concept, invented by Kenneth Snelson and made famous by the architect Buckminster Fuller in 1949.


Exothermic Crystallization Heat Pack

Available in many sizes and colors: 
From Educational Innovations: BUY NOW Click Activated Resuable Heat Pack 
From Amazon: BUY NOW Click Activated Reusable Heat Pack 

Exothermic Crystallization Heat Pack: real-time instant crystallization of a supercooled solution. Solid sodium acetate melts at 137F (58C), but it will stay in liquid form as it cools to room temperature creating a supersaturated and supercooled state- the solution stays in the liquid form until a seed crystal, provided by clicking the metal disk, initiates the solidification. The resulting white crystal is actually quite hot; solid states have lower energy than liquid states and thus the difference in energy is given up as heat that raises the temperature back up to the melting temp, and you can see in the few seconds of the video that the temperature rises from 26C to 34C. This pack is reusable many times- just boil the pack until all the crystal is melted to reset. 

Thermochromic Safety Sticker

These stickers transition back and forth and can be used on many surfaces. Get some here:

physicsfunshop: BUY NOW: Thermochromic Saftey Sticker

Thermochromic Safety Sticker: the liquid crystal ester dye in this reusable sticker is calibrated to change color when the surface temperature exceeds 50°C (122°F)- that at which prolonged contact (more than 0.5s) will burn skin. Here the safety sticker is attached to a slab of aluminum and heated with a simple candle- it took about 3.5 minutes for the heat to distribute and bring the aluminum to the threshold temperature. When the surface cools the sticker again appears blank and can transition over and over again

Heat Pipe

The heat pipe kit includes the pipe and a copper rod: 
From Educational Innovations: BUY NOW Heat Pipe Demo Kit 

Here is the liquid crystal sheet used in the video (range 20-25C): 
From Educational Innovations: BUY NOW liquid crystal thermometer sheet 

Heat Pipe: a device that transfers heat with great efficiency- as demonstrated by this fantastic kit from @educational_innovations . Here a liquid crystal goes from green (room temp) to black (near freezing) showing the heat transfer to a piece of ice through a heat pipe (top) and a similar sized piece of solid copper rod (bottom). As you can see the heat pipe cools much faster than the copper rod even though copper is an excellent conductor of heat. The heat pipe is a thin shell of copper that surrounds a tube of sponge like material filled with some water vapor and sealed with a low pressure inside. The heat is transferred from one end to the other by the phase transition of water- at the warm end water in the sponge evaporates into vapor absorbing heat energy, the vapor travels down the hollow core to the cold end where it condenses into liquid releasing heat energy. The water is wicked by the sponge to the warm end and the process repeats. Heat pipes like this one pull heat away from the CPUs in modern computers preventing them from melting. The amazing heat transfer ability is clearly felt in the fingertips if one places the copper rod and heat pipe into a glass of ice water-the heat pipe immediately gets cold! 


Fluorescence and Birefringence in Calcite

Get a sample here: 

From eBay: BUY NOW Optical Calcite Crystal 
From Amazon: BUY NOW Optical Calcite Crystal 

Get inexpensive polarizing filters here: 
From Educational Innovations: BUY NOW Polarizing Filter Sheets

Need a UV laser pointer? Get 3 lasers (one of each color) for under $10 (including S&H): 
From eBay: BUY NOW red+green+blue(UV) laser pointers

Fluorescence and Birefringence in Calcite: two samples of calcite- each with different impurities that produce blue fluorescence for the small crystal and red fluorescence for the larger one under a 405nm violet laser. Also one can clearly see that the single laser beam takes two paths through the crystals- the speed of light in a calcite crystal depends on polarization because the refractive index is different depending on the polarization orientation of the light transmitted through it (swipe for demonstration). As a polarizing filter is rotated 90 degrees, one image appears and the other vanishes, showing that the polarization orientation of the light of the two images is indeed perpendicular. In addition the elegant rhombohedral nature of calcite crystals is obvious in this sample.

Nixie Tube 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 Clock: 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. 

Feel Flux Loop

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

From feelflux.com: 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.


Glow Trace Chaotic Pendulum Kit

Get this super nice, affordable, and fun to assemble kit here:
From KiwiCo: BUY NOW: Glow Pendulum Kit

Get amazing quatilty science kits delievered to your home- this glow pendulum is part of the Tinker Crate subscription. 
From KiwiCo: LEARN MORE: Tinker Crate Subscription

Glow Trace Chaotic Pendulum: this fun and DIY kit features a UV diode to trace the intricate path of this double pendulum system on to a phosphorescent screen, revealing the physics of chaotic motion. It’s amazing that such complex motion can arise from a simple assembly of two pendulums, one attached to the end of the other. Chaotic motion, such as that observed here, is characterized by extreme sensitivity to initial starting conditions, tiny differences in how the system is released leads to dramatically different outcomes each time. 

 

Penrose Aperiodic Rhombs

This set avaiable here:
From : Search NOW Penrose P3 Tiling
Wikipedia has the details on Penrose Tilings and their inventor Sir Roger Penrose (Recently won Nobel Prize!) 
Another nice version of Penrose Tilings is available here: 
From Etsy: BUY NOW Penrose Tiles 

Penrose Aperiodic Rhombs: a famous aperiodic tiling with just two shapes- a pair of rhombuses with equal sides, but with the ratio of their areas made to equal the golden ratio. Note that although the starting pattern of 10 tiles is symmetrical, adding any further tiles breaks the symmetry, as highlighted by the path of the double curves. Sir Roger Penrose- who just won the Nobel prize in physics for his contributions to General Relativity- also discovered tessellations (tilings) that are aperiodic even though the two tile types are regularly shaped polygons. If one tries to shift a part of a Penrose tiling, the shifted part will not align or match up with any other part of the same tiling- all the way out to infinity! In this construction, single and double line patterns must align such that the tiles can only connect in specific ways to ensure the non-repetitive nature of the Penrose tiling structure. Shown here is one way these two tile types will fill the plane.

The Random Walker

Galton Board version available here: 
From Amazon: BUY NOW 
Galton Board 

The Random Walker: second model of two Galton Boards designed and produced by IFA.com- this version is made to demonstrate probability in investment returns of a global stock market portfolio relating to risk capacity. Slow motion reveals the erratic path of each steel ball (second half of video). The red graph shows the distribution of 592 monthly returns (mean =1%, SD=5%) representing data from 50 years of an IFA Index fund- here the random “walk” of 3000 steel balls falling through 12 levels of branching paths always produce a close match, and both distributions tend toward the famous bell curve distribution. A wonderfully designed modern version of the Galton Box invented by Sir Francis Galton(1894) to demonstrate the Central Limit Theorem - showing how random processes gather around the mean.


Penrose Tiling Puzzle

This puzzle was produced and sold in the 1990s. 
The individual tiles can be found on eBay (and sometimes the whole puzzle): 

From eBay: Search NOW Penrose Pentaplex Puzzle 
Wikipedia has the details on Penrose Tilings and their inventor Sir Roger Penrose (Recently won Nobel Prize!) 
A nice basic version of Penrose Tilings is available here: 
From Etsy: BUY NOW Penrose Tiles 

Penrose Tiling Puzzle: a challenging puzzle with pieces that come in only two shapes. Sir Roger Penrose- who just yesterday won the Nobel prize in physics for his contributions to General Relativity- also discovered tessellations (tilings) that are aperiodic even though the two tile types are regularly shaped polygons. If one tries to shift a part of a Penrose tiling, the shifted part will not align or match up with any other part of the same tiling- all the way out to infinity! This puzzle, entitled “Perplexing Poultry”, created and sold by Penrose himself, uses polygons modified into crazy looking birds such that the tiles can only connect in specific ways to ensure the non-repetitive nature of the Penrose tiling structure. Shown here is one way these two tile types will fill the plane.

Arrow on Mobius Strip

Get this 3D printed object of math topology here:

From Etsy: BUY NOW: Mobius Strip with Arrow

Arrow on Möbius Strip: on the geometry of a Möbius strip a right pointing arrow points left after one trip around, a second trip restores the original orientation. This mathematical property is called non-orientability, and is also true of Klein bottles which I’ve posted about. I love how this 3D printed model, designed and produced by Wes Pegden, allows one to physically manipulate and intuit this somewhat obscure mathematical property. 

Ambiguous Object Illusion Set

This wonderful and afffordabe set includes four illusion objects and a mirror:

From curiositybox.com: BUY NOW: Inq's Ambiguous Illusion Kit

Ambiguous Object Illusion Set: finally a set of these fantastic physical illusion objects available in the US for purchase. This kit comes with four objects (three shown here) invented by mathematician Kokichi Sugihara of Meiji University in Japan. Polygons appear as circles in a mirror and vice versa, and the famous “stubborn arrow” that will only point to the right (or, in a mirror, to the left). I like how the base is also an ambiguous pentagon/circle, which like all these objects, is a result of a clever combination of reflection, perspective, and viewing angle. Thanks to the Vsauce team for producing this kit! 


Light Pipe Sculpture

Get an affordable pre-bent light pipe demo here:
From Amazon: BUY NOW: Light Pipe Demo

Blue laser pointers (445nm) available here:
From eBay: BUY NOW: Blue Laser
but any color laser will work. 

Make your own abstract light pipe sculpture, an inexpesive heat gun is the only needed tool:
Materials from eBay: BUY NOW: Acrylic Rod
Tool from Amazon: BUY NOW: Heat Gun

Light Pipe Sculpture: internal reflection constrains most of the laser light to propagate along the bent acrylic rod- the physics of fiber optics. This abstract sculpture was created by applying a heat gun to a 3/8” diameter acrylic rod. The laser pointer used here is blue at a wavelength of 445nm.

Enantiomorphic Rattelback Pair

Get this mirror-image pair here: 

From curiositybox.com: BUY NOW: Enantiomorphic Rattlebacks

Enantiomorphic Rattleback Pair: one reverses to always spin clockwise, the other reverses to spin counter-clockwise. This behavior is related to the asymmetric shape of the bottom of this kind of rattleback, each is somewhat propeller shaped with an "S" curve along the bottom ridge. This pair are mirror images of each other (enantiomorphs) in terms of shape. When set to spin a reversal can take place due to a complicated combination of friction, precession, and instability induced vibrations which will transform the rotational energy into into rattling (energy of oscillations) and then into rotational energy in the opposite direction! Thanks to team Vsauce for bringing this set into existence.

 

Precision Tippe Top

Get a flip over tippe-top here:   

STEMcell Science Shop: BUY NOW Tippe-Tops 

Precision Tippe-Top: spinning things often have surprising physics! This aluminum version of the famous flip-over top works better than any I’ve seen. Friction with the desk surface provides a torque that acts on the existing angular momentum of the top to flip it over. The top will stay flipped until the spin rate slows down enough to where its center of mass pulls it back to the resting position.