Matsuyama's Paradox
Get this and other amazing math puzzles here:
From Etsy: BUY NOW: Missing Square Puzzle
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Matsuyama’s Paradox: dissect a large square in to four equal quadrilaterals, rotate and reassemble- to find a small square is missing! Where did the additional area come from? Fun math involved in the design of this puzzle, which illustrates how the concept of area can often challenge our intuitions. Swipe to compare the two assemblies. A precision crafted puzzle by Jeux Efcé game shop. Wikipedia has good details: Missing square puzzle.
Wringing Guage Blocks
Guage block sets can be a bit pricy, but some fairly inexpensive pieces and small sets can be found for demonstrations and such:
From Amazon: BUY NOW: Gauge Blocks
Wikipedia has a nice description of Gauge Blocks and the Phenomenon of Wringing
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Wringing Gauge Blocks: two blocks of metal (not magnets!) will stick together by a process called wringing if their surfaces are flat to high precision- such as these gauge blocks found in most machine shops. Here two blocks are forced apart with a snap, and then wrung back together with the characteristic sliding motion technique. Gauge blocks are flat to less that one millionth of a meter and are used by machinists for precision length measurements and calibration. The science of the wring force remains somewhat a mystery and no one has yet found a fully excepted physics description- but we do know that blocks will wring in a vacuum and that the force can be up to 30 times that of weight of the blocks. Fun physics from the shop!
Levitation Lamp
Get this fun lamp here:
From Amazon: BUY NOW: Levitation Lamp White, Levitation Lamp Black
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Levitation Lamp: tapping the floating spherical magnet turns this LED lamp off and on in this interesting design. The 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.
Galileo Drop Tubes
This set of glass demonstration tubes comes from Germany and is available here:
From experimentis Shop: BUY NOW: Galileo Tubes
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Galileo Drop Tubes: in a partial vacuum (left tube), paper confetti and balls of lead shot fall together and hit the bottom at the same time- as Galileo predicted some 400 years ago! The tube on the right has air at standard pressure, the left tube is at a partial vacuum similar to that of a light bulb. In slow motion one can see that the bits of paper fall at the same rate as lead shot when the effects of air resistance are reduced, showing that all objects fall with an acceleration of g=9.8 m/s2 near the Earth’s surface.
H6 Chondrite Meteorite
Own a piece of space rock! Afordable meteorties of many types and sizes:
From Etsy: BUY NOW: Meteorite Specimens
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H6 Chondrite Meteorite: identification of rocks that fell from space- H6 chondrites are stony iron meteorites with a high percentage of nickel-iron in the form of little spherical blobs called chondrules. Chondrules are only found in meteorites- and you can see that some of them are protruding from the surface of this specimen as little shiny bumps. H6 meteorites are so full of these that they will be strongly attracted to a magnet. Over one third of all classified meteorites are such H Chondrites, and a great way to find a rock from space is with a magnet on the end of a stick!
Anamorphic Harry Potter Puzzle
No longer in production but available on eBay:
From eBay: BUY NOW: Harry Potter On Reflection Puzzle
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Mirror Anamorphic Harry Potter: the conical mirror of the silver container reflects and reveals the distorted scenes in this 200 piece jigsaw puzzle of the famous wizard and school. The shape of the mirror allows for a mathematical operation, a type of affine transformation, to map the distorted image of the puzzle to the restored image reflected by the mirror. Real magic!
The DeltaCELT Rattleback
Get one here:
From Etsy: BUY NOW: The DeltaCELT
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The DeltaCELT: a new rattleback design where the indentations create an asymmetry in the distribution of mass that leads to rotation reversals when spun: 1) If spun clockwise, after about two full rotations, a complicated combination of friction, precession, and instability induced vibrations transforms the rotational energy into into end-to-end rattling (energy of oscillations) and then into rotational energy in the opposite direction. 2) If spun counter-clockwise, after about 30 full rotations the rotational energy translates into side-to-side oscillations leading to a clockwise reversal (swipe to see- less dramatic but still amazing). The design is made of solid brass and has the shape of a bisected prolate ellipsoid in the proportion of the mathematical constant δ =4.669.. (Feigenbaum dynamical constant) giving the name to this new design by astrophysicist Kenneth Brecher. The DeltaCELT comes with the polished slate spinning surface for optimal performance.
Gosper Fractal Fidget
The 3D Print files are available here:
From Printables: Download Now: Gosper Fractal Fidget
Gosper Fractal Fidget: exploring geometry and elasticity. For any given shape of elastic ribbon what would it look like if flipped inside-out? Surprising results often follow. I received this amazing item in the G4G gift exchange at the Gathering for Gardner conference back in February. Designed and printed by Thomas Draper
Glass Hydro-Top
Available in four colors and designs:
BUY NOW: Glass Water Tops
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Glass Hydro-Top: under centripetal acceleration a liquid will flow to create a cylindrical surface parallel to the axis of rotation. This blown glass dreidel contains a small amount of colored water that when spun resembles a blue gemstone banded around the rim. A unique design with fun physics!
Vortex Pyramid Fidget
Get this kinetic object here:
From ETSY: BUY NOW: Vortex Pyramid Passthrough Fidget
or use these files to print it uourself:
From Printables: Download Now: Pyramid Passthrough Fidget
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Vortex Pyramid Fidget: a four sided pyramid is dissected by a spiral cut in the shape of an eight petal flower (as seen from the bottom) in this math inspired kinetic toy. The interesting behavior stems from the connection between translational motion and rotational motion and the precision manufacturing allowed by the 3D printing process. An amazing creation by RJ Design and expertly printed by my friend Jason Veatch.
Diffractive Optical Element
Amazing application of high resolution far field holograms. The only available source I know of for projection holograms at this high resolution is this supplier of industrial samples
From MaterialSampleShop.com: Diffractive Optical Element Sample
Need a laser pointer? Incredibly, you can get 3 (one of each color) for under $20 (including S&H):
From Amazon: BUY NOW Red+Green+Purple Laser Pointer
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Diffractive Optical Element: images produced by constructive and deconstructive interference of coherent laser light. The patches of microstructure on the surface of this transparent plastic are far field holograms- transmission holograms, but with the image at infinity. Side by side images from two different laser wavelengths (red 635 nm, green 520 nm) shows clearly the red image is larger than the green since diffraction angle is proportional the wavelength. So much physics here!
Photochromic UV Bracelets
Get similar bracelets here:
From Etsy: BUY NOW: UV Color Change Bracelets
You may also want an awesome UV flashlight like this one:
From Amazon: BUY NOW: High Power UV Light
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Check out this: Photochromic Frisbee
UV Color Changing Beads: the photochromic pigment molecules in the white beads actually change shape when struck by UV light, and the new shape alters their absorption properties such that they reflect brilliant colors. The color is temporary- when removed from UV exposure, room temperature thermal energy bumps the molecules back into their original configuration, and the color fades back to white in a few minutes. Here a UV flashlight reveals that each bracelet transforms to a different color.
Kitty Cat Fireworks Lamp
Variations (bear, spaceman) avaialable from these sources:
From Etsy: BUY NOW Fireworks Infinity Lamps
From Amazon: BUY NOW Fireworks Infinity Lamps
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The Kitty Cat Lamp I found: here
Kitty Cat Fireworks Lamp: illusion of depth from multiple refections. This glass cat sculpture is partially coated inside and out with a thin metal layer. The metal layer is made thinner in a pattern of small circles and stars to produce iridescent colors through thin-film interference effects. When lit from within by white LEDs, multiple reflections on the curved contour of the glass creates the firework like spray of light and color.
Wire EDM Puzzle Cube
Get this piece of machine art here:
From ETSY: BUY NOW: EDM Puzzle Cube
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Wire EDM Puzzle Cube: art from precision metalworking technology- a wire EDM (electrical discharge machine) can cut into solid stainless steel and leave a gap of less than 0.05mm between the remaining pieces. Here a 1.5 inch cube is dissected into 4 jigsaw style pieces that slip together with barely a seam.The EDM process, sometimes called spark machining, removes material from the work piece by a series of rapid current pulses, that when bathed in dielectric liquid creates electric arcs that “vaporize” a precise bit of metal with every pulse.
Gear Ball
Get the print files here:
From Thangs: Download Now: Gear Ball
Or get one printed in the color(s) of your choice:
From Etsy: BUY NOW: Gear Ball
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Gear Ball: another amazing gear assembly with an abstract geometry that would be very hard to make without 3D printing with four large and four small conical cogs. A super fun creation by maker/designer Ruven Bals.
MSG-! Martian Soil Simulant
Start your own physics toy collection with a subscrition to the Curiosity Box
Simialr soil simulant: MMS-2 Mars Regolith Simulant developed by the Exolith Lab at University of Central Florida
From STEMcell Science: BUY NOW: Martian Soil Simulant Sample
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MSG-1 Martian Soil Simulant: if you could scoop up a handful of Mars near the Gale Crater landing site this is what the dirt of the Red Planet would look like up close! Produced by NASA for engineering studies of future robotic rover and human activities on Mars, this simulated regolith closely approximates the chemical, mineral, and grain size distribution based on data from NASA’s Curiosity Rover.
Meteorite: Rock from Mars
Get a piece of Martian Meteorite here:
From AEtsy: BUY NOW: Martian Meteorite Sample
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Here is the offcial data on this particular meteorite: NWA 12269
How do we know it's from Mars? Here's a good overview of the science.
Rock from Mars: an actual chunk of the Martian surface, a piece that was splashed into space long ago when an asteroid impacted Mars. In fact, the Mojave crater on Mars (3M years old, 60km in diameter) has been identified by researchers as the potential source of the rock you see here- designated NWA 12269, a type of Martian meteorite called a shergottite. This is a 1.01g polished slice of the original 1.7kg meteorite which was found in 2018 Africa. Of the 65000+ classified meteorites in scientific databases, only 298 are known to have come from the Mars.
Flo-Motion Lamp
These viintage lamps are often available from these sources:
From Etsy: BUY NOW: Flo-Motion Lamp
From eBay: BUY NOW: Flo-Motion Lamp
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Flo-Motion Lamp: a vintage 1990s vortex lamp filled with rheoscopic fluid. When the light is on a motor turns a plastic spiral screw within the cylindrical volume to create the rotational turbulent flow which is made visible with tiny flake crystals of mica catching the light in the special fluid. Rheoscopic fluids were developed by Paul Matisse in the 1970s to allow visualization of fluid motion. These lamps are available on auction sites but most are missing some of the fluid through years of evaporation. I found this one and had to add water in what turned out to be a pretty simple repair.