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Maxwell's Top

Available from my friends at Grand Illusions Ltd.: 
From Grand Illusions: BUY NOW Maxwell's Top with Spiral 

Maxwell’s Top: a new miniature version of one of my favorite demonstrations of the strange properties of rotating bodies- based on a famous experiment by the great physicist James Clerk Maxwell. When this bell shaped brass top is spinning an interesting stability can occur- push on the stem with an object and the top will push back, forcing the stem against that object, and friction will cause the stem to roll along and trace the edge of the object. In this design the stem will trace along the edge of a metal spiral, clinging to it like a magnet- but magnets are NOT involved here. The key to this design is to make the contact point/tip of the top at its own center of mass, then any frictional force in contact with the stem will produce a torque about the contact point at right angle to the direction of friction that creates the stabilizing force (students of physics may recognize application of the right hand rule here). An extreme physics toy- beautifully designed and crafted by Kontax Engineering Ltd

Vacuum Engine 

Get this amazing engine here:

From EngineDIY: BUY NOW: Vacuum Flame Licker Engine

Flame Eater Engine: also called a vacuum engine- operates by opening a valve during the piston intake stroke to pull in a bit of burning gas from the flame- the valve closes and the trapped hot gas expands pushing the piston. The exhaust stroke then has the gas cool, contract, and get pushed out the same valve right before the process repeats. Slow motion captures the intake of the flame through the valve/mouth at the cylinder head which gives the appearance that flame is being chewed- hence the name. Note this engine design does not need to warm up and starts instantly, but is very inefficient as only a fraction of the burning fuel (alcohol) is used by the thermodynamic process each cycle. 

Crushmetric Pen: Galactic Black

Availabel here:

From BUY NOW: Crushmetric Pens

Crushmetric Pen: the Switch Pen, Galactic Black foil edition- functional kinetic art based on materials science and tessellation origami techniques. The crushed state can be reversed over and over in this incredible design by artist/inventor Noah Deledda @noahdeledda, also known for his similar sculptures created from aluminum cans. Wonderful and affordable kinetic art object that is a practical ballpoint pen.

Chaotic Decision Pendulum

Get this device here:

From eBay: BUY NOW: Chaotic Decision-Aider Pendulum

From Amazon: BUY NOW: Chaotic Decision-Aider Pendulum

Chaotic Decision Maker Pendulum: adding magnetic forces to gravity gives this comical pointing pendulum chaotic motion- not random, but very sensitive to slight differences in initial launch conditions. Each “choice” has a dipole magnet underneath which attracts a magnet in the hand and locks the pointer into place, but only after enough kinetic has been dissipated, and until that final state is obtained the motion is chaotic. Fun physics behind this novelty gag gift.

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!

Alexandrite Effect

Similar color change gemstones available here:
From Etsy: BUY NOW: Synthetic Alexandrite
Explore propperties of minerals and gemstones with this fun jeweler's flashlight:
From Amazon: BUY NOW: Jeweler's Appraisal Flashlight

Alexandrite Effect: dramatic color change under different light sources- seen here first under halogen incandescent light and then under cool white LED (similar to sunlight), due to selective absorption of frequencies of visible light. These two faceted crystals are synthetic gems, Tourmalike and Tourmalike+, that dramatically exhibit this effect especially under the illumination of this jeweler’s appraisal lamp that allows one to select white light with different spectra (and also UV). This phenomenon is named for the famous (and expensive) alexandrite gemstone variety of the mineral chrysoberyl.

Coin Escape Puzzle

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

From Grand Illusions: 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. 

Pikachu Phonotrope Spinner

Get similar amazing spinners here:

From Etsy: BUY NOW: Animation Spinners

Phonotrope Spinner: When viewed through video from a smartphone an animated Pikachu springs into motion. The laser cut and printed acrylic is specifically designed to interact with the frame rate of the video process, similar to the animation effect of a flip book, but in a repeating cycle. The effect can also be seen without a camera by using a mirror and viewing through the spaces between the cutouts. Using a mirror like this turns the spinner into a phenakistiscope, the 1833 invention that started moving media animation that lead to the development of movies and video. 

Centripetal Switch

Get a siimilar light up top here:

From Amazon: BUY NOW: light up spin top

Centripetal Switch: a very simple design allows sustained power to the LED only when the top is spinning. A floppy spring is attached to one side of the LED and when the top is spinning centripetal acceleration bends the spring to touch the metal flange to complete the circuit. Note that in operation the LED is not on the whole time, but flashes on and off due to vibrations affecting the simple spring switch contact, and when coupled with the frame rate of the camera, creates the light patterns seen here. Simple design, but lots of physics! 

RGB Additive Color Mixing Demo

Get this inexpensive demo here:
From eBay: BUY NOW: RGB Color Mixing Demonstration

Wikipedia has a fantastic introduction on the topic of RGB Color Theory 

RGB Additive Color Mixing Demo: three LEDs projected onto a translucent screen demonstrate the additive nature of our perception of colored light. Three potentiometers allows the user to adjust the intensity of each color. Mixing Red, Green, and Blue to create Yellow, Magenta, and Cyan with the following mixings: R+G=Y, G+B=C, and R+B=M. Adding all three R+G+B produces White. RGB color addition is the basis for all computer and TV displays- all the colors you are looking at right now on your screen are made from adding pixels of R G and B in different proportions and intensities!

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. 

Color Enhanced Lithophane: Escher Dragon

Get a color lithiphane here: (the dragon or photo of your choice)

From Etsy: BUY NOW: 3D printed full color lithophane

Lithophane Color Escher Print: another modern take on the lithophane technique from the 1820s- this time with color changing LEDs and again via modern 3D printing that allows full color images through selective absorption and transmission of light. This lithophane was created using a photo of my black light poster (featured two posts back). Traditional lithophanes produced gray tone images by shining light through a translucent substance, initially porcelain, where thicker regions absorb the light and appear dark gray, and thinner regions look light gray. 3D printing allows a new method for producing this art form with amazing detail, where layers of colored plastic, applied in the right sequences and thicknesses, can produce lifelike and artistic results. Yet another amazing 3D print by Alex L. Kling!

3-Shuttle Trammel of Archimedes

This device came in my Curiosity Box subscrition. A great way to start collecting your own physics toys (and other brain food):

From the Vsauce team: BUY NOW: The Curiosity Box (New box will ship soon- get a great deal now)

Get similar (two shuttle) devices here: 

From Etsy: BUY NOW 
Trammel of Archimedes

3-Shuttle Trammel of Archimedes: as the shuttles take turns completing their straight line journeys, the end of the crank arm traces an ellipse. This precision 3-shuttle version by the VSauce team came in my @thecuriositybox - made with high quality molded plastic parts that produce very smooth movement- a wonderful addition to my collection! Sometimes sold as a “do nothing machine” or “nothing grinder”, far from doing nothing this simple and crucially important mechanism demonstrates how rotational motion can be converted into translational oscillatory motion- such as how a piston can drive an engine’s crankshaft.


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. 

Moon Rock: Lunar Meteorite 

Get a piece of Lunar Meteorite from this reliable dealer:

From eBay: BUY NOW: Lunar Meteorite Sample

Here is the offcial data on this particular meteorite: Tisserlitine 001

How do we know it's from the Moon? Here's a good overview of the science. 

Moon Rock: an actual chunk of the lunar surface, a piece of regolith breccia that was splashed into space long ago when an asteroid cratered into the Moon- a process not too uncommon as the escape velocity of the Moon is quite small. This piece went into orbit around the Earth and finally fell from the sky to land in Mali Africa. The lunar origin of this meteorite (found in 2019 and designated Tisserlitine 001) is well established: it is made of the exact same minerals as the moon rocks brought back by the Apollo missions, importantly it has zero content of any of the most common Earth minerals, and the internal structure of the grain size distribution is fractal unlike any rocks formed on Earth (which feature geological sorting from erosion and stronger gravity- processes that don’t happen on the Moon). These and many other chemical and physical tests confirm the lunar origin of this sample. Of the 65000+ classified meteorites in scientific databases, only 436 are known to have come from the Moon. Amazingly, small pieces of these meteorites, like this sample shown here, can be purchased. 

Vintage Blacklight Poster: Escher

Fun vintage posters can be found here: 

From eBay: BUY NOW: Blacklight Poster Escher

From Etsy: BUY NOW: Blacklight Poster Escher

Vintage Blacklight Poster: a stunning psychedelic era poster from 1971 glows brightly under a vintage blacklight from the same year. This amazing silkscreen uses fluorescent pigments (new tech in the 1960s) that absorb ultraviolet light and then re-emit the energy in visible photons. Design based on M. C. Escher’s black and white 1952 wood engraving print “Dragon”. 

Am-241 in Wilson Cloud Chamber

I found this vintage apparatus on eBay. Here is a similar device made for classroom demonstrations (a bit pricey though): 
From 3B Scientific: BUY NOW Wilson Cloud Chamber 

Diffusion cloud chambers that use dry ice are more affordable: 
From eBay: BUY NOW Diffusion Cloud Chamber 

Wikipedia has nice descriptions of Am-241 and the history and operation of Wilson Cloud Chambers 

Am-241 in Wilson Cloud Chamber: the typically invisible ionization tracks of alpha particles emitted from a radioactive source are revealed in this miniature expansion type cloud chamber. When an americium nuclei disintegrates it ejects a high speed cluster of protons and neutrons (2 of each) called an alpha particle which then plows through the air creating a trail of ions, tearing electrons off any nearby molecules it passes by. A rapid decrease of pressure (releasing the squeeze bulb) drops the temperature in this chamber allowing cloud formation. Alcohol droplets prefer to condense on ionized molecules/atoms and so reveal the tracks. Amazingly the synthetic element americium-241 is found in common smoke detectors, where a few micrograms will emit thousands of alphas per second. Of course please use great caution if you choose to mess around with any Am-241- it’s safe inside the smoke detector, much less so if removed.