I made this set of tumble rings from reading Martin Gardner's description in his famous mathematical recreations books- highly recommended:
From Amazon: BUY NOW Knots and Borromean Rings by Martin GardnerDescribes the Tumble Rings
From Amazon: BUY NOW Books on recreational math and puzzles by Martin Gardner Lots of physics and math toys in these pages!
Tumble Rings: the links in this chain are connected in a special way such that the top ring appears to tumble to the bottom- a compelling illusion!
From MovaGlobes.com: BUY NOW Pluto MOVA Globe
Wikipedia has a wonderful summary of the 2015 Pluto flyby and the complete mission of the New Horizons space probe.
Pluto Globe by MOVA: simulate the historic 2015 Pluto flyby of NASA’s New Horizons space probe with this self rotating detailed image of the dwarf planet’s surface. Each MOVA rotating globe is sealed within a clear liquid filled acrylic sphere. The rotation is powered by light that shines through the semi-transparent Pluto globe on to solar cells inside the globe which drive a motor. But what does the motor push against to maintain the rotation? Believe it or not it uses magnets to push against the Earth's magnetic field like a compass needle. Love this clever device. With thanks to @movaglobes for sending me this amazing globe.
This vintage item is out of production. Here are some similar times based on whirlpool vorteces:
From Amazon: BUY NOW Vortex Lamps
"Pet Tornado": whirlpool powered by a magnetic stirrer (like those in a chemistry lab). The knob on the side has settings F1 through F5 ? One of my sillier toys- but vortices are just so cool.
If you are ever in Florence be sure to visit the Galileo Museum and see the original- as well as a collection of Galileo's telescopes and experiments.
Visit: Museo Galileo
Optical Trick Portraits: Hold a flat mirror up to this painting of Charles III, Duke of Lorraine, to reveal his daughter Christina in this 1593 work by Ludovico Buti. A very early example of lenticular images, Gioco Ottico hangs in the Galileo Museum in Florence as part of the Medici Collections. I got this toy version from the museum gift shop a couple months ago.
Get this mini prehistoric balance beast here:
From Amazon: BUY NOW Balance Pterosaur
Mini Balance Pterosaur: weights in the forward wing tips create a center of mass below this pterosaur's beak- making a system that can rotate and oscillate about a stable equilibrium condition. No magnets used or needed for this physics! Usually this toy is found in the form of a bird (direct dinosaur descendent). Pterosaurs are not dinosaurs, but are the largest animals to ever fly, and powered flight has only evolved four times: bats, birds, pterosaurs, and insects- in reverse order.
Get a set of Reuleaux solids here:
From Shapeways: BUY NOW Volumes of Constant Width
Volumes of Constant Width: these shapes have constant diameter no matter their orientation and will roll like spheres between two planes- note how the acrylic plate stays parallel to the table top. Two of these three solids are based on the Reuleaux triangle and the other on a Reuleaux pentagon.
Similar vintage items like this one are sometimes found on eBay and Etsy:
From eBay: BUY NOW paper slinky kinetic art
Paper Spring Kinetic Art: vintage piece of manipulable art by Henry Adams that utilizes the elastic properties of paper in a honeycomb configuration. Magnets on each end allow for a closed loop and a kaleidoscope like effect as the piece is turned inside-out. "Playart" circa 1989.
This sculpture and others available here:
From eBay: BUY NOW Steinbach Reflection Scupltures
Reflection Symmetry Sculpture: precision etched into one side of a triangular prism, multiple reflections within the optical grade glass create the 3D castle and grounds. Fun use of symmetry and geometry in this optical crystal sculpture series by Steinbach.
See more illusion art from Victoria Skye here:
From victoriaskye.com: Illusion and Impossible Objects
Skye Blue Café Wall Illusion: the horizontal blue lines appear to be sloped but they are actually parallel, as verified by sighting a straight line from the edge of the image. This visual illusion is related to the level of contrast between sharp boundaries, and if the boundaries are blurred (here with a plate of frosted glass) the illusion is broken and the lines appear parallel. Note that even after we verify the lines are parallel, our perception still misleads- a reminder that we need science to transcend the limits of our senses and cognition. This award winning illusion was created by artist Victoria Skye and is featured here with permission. @vicskye
The best effect (highest fountain) is obtained by using #10 size chain with a bead diameter of 3/16" (4.8mm). This spool has 100 feet of chain, the same length as used in the video.
From Amazon: BUY NOW #10 ball chain
Wikipedia has the details on the discovery of the chain fountain, and for those that want the physics here is the paper: Understanding the Chain Fountain from Proceedings of the Royal Society A, 2014
Chain Fountain: as the chain flows out of the glass under the pull of gravity the beads don't simply roll over the edge but instead arc up upward like a fountain. As each link is pulled and tilted upward the adjacent link is tilted downward and pressed into the pile- by Newton's 3rd law the pile presses back pushing each bead upward into the air. A segment of the video is shown in slow motion where the fountain is at maximum height. This phenomena was recently discovered by Steve Mould (more to be seen at his YouTube channel) and the details of the physics is described in the Proceedings of the Royal Society by Biggins & Warner (2014).
Another science toy from Taiwan! Produced by the Mr. Sci Science Toy Factory
From Mr. Sci Science Toy Factory: Buy Now Civilized Glass
Learn more about the Pythagorean Cup on Wikipedia
The Civilized Glass: a most elegant version of the famous Pythagorean cup. Functions as a normal glass, but if the glass is filled above the top of the central column a siphoning effect is triggered and all the contents in the glass drains out the bottom through the hollow stem. With this glass moderation is key! This well made glass design by @mrscisciencefactory allows one to see the mechanism of the siphon tube usually hidden in ceramics
These are hard to find--
also beware that some versions of this cup (Dragonware) contain images many would consider "adult content"!
I recommend making one with a shot glass and a marble as described in this fun collection of DIY science experiments by Martin Gardner:
From Amazon: BUY NOW Science Fun by Martin Gardner
Magic Sake Cup: when this antique ceramic sakasuki is filled with clear liquid an image of a bride is revealed! The spherical glass lens at the bottom has a very long focal length in air, but when immersed in water the glass marble has the same focal length as a magnifying glass, unveiling the portrait. Refraction depends heavily on the refractive index of the two transparent mediums.
Made by American Paper Optics Inc. All versions of these holographic glasses can be found here:
from Amazon: BUY NOW Wild Eyes 3D Glasses
Here is a good description of the physics and principles of operation of these far-field holograms by the manufacturer HoloSpex, Inc.
Need a laser pointer? Incredibly, you can get 3 (one of each color) for under $10 (including S&H):
From eBay: BUY NOW Red+Green+Purple Laser Pointer
Wild Eyes Holographic Glasses: put on these goggles and on top of every point-source of light will appear an animated holographic image of sharks swimming. (Here I used a Maglite flashlight with the cap removed.) The "lenses" in these glasses are actually transmission holograms with the image located at the farthest point in the depth of field. In this version there are three holographic images in a trifocal glasses arrangement- tilting one's head brings the animation to life! Holographic glasses can also be used to project an image using the beam of a laser- the very same technology used to make the "projection caps" on inexpensive laser pointers. Made by American Paper Optics LLC.
Many versions of this kaleidoscope are available:
From Amazon: BUY NOW Fluid Flow Kaleidoscope
From eBay: Fluid Flow Kaleidoscope
UV Fluid Flow Kaleidoscope: original glitter wand kaleidoscope made by Illusions back in the 1990s. Intricate geometry from multiple reflections coupled with the viscous fluid motion of the glitter produces this psychedelic kinetic art. Under the illumination of a UV light this version takes it to the next level featuring fluorescent pieces and phosphorescent stars in the fluid of the wand.
These coasters are almost sold out everywhere: only The Mona Lisa is still in stock:
From Amazon: BUY NOW CMYK Coasters
From eBay: BUY NOW CMYK coasters
The CMYK model and colorspace on Wikipedia.
CMYK Coasters: physics and psychophysics of four color printing demonstrated with acrylic slides that assemble to reveal Vermeer's "Girl with a Pearl Earring". Cyan, magenta, yellow, and black (key) comprise the elements of the subtractive color model used in most color printing. Repost of the “most liked” post of 2016!
One of many amazing and accurate models made by Theodore Gray:
From MechanicalGifs.com: BUY NOW Pin-Tumbler Lock Acrylic Model Kit
Pin-Tumbler Lock: simple and accurate model of how a basic lock works. The pins (orange/green) are held in place with springs and keep the tumbler from sliding and releasing the chain. The contour cut into the edge of the key must match the lengths of the green parts of the pins. When the key is inserted, the edges of the green pins line up allowing the tumbler to slide, unlocking the chain. In most locks the tumbler rotates instead of sliding, but the principle is the same. One of many “Transparently Obvious” models in the Mechanical Gifs series created by Theodore Gray.
Get one here!
From Amazon: BUY NOW Cartesian Divers
Cartesian Diver: increasing pressure on the water compresses the air bubble in the small plastic vial (here in the shape of an octopus' head) filling it further with water and making the diver sink. Pascal's principle states that any change in pressure on an enclosed fluid (such as squeezing the plastic bottle) is transmitted evenly to every part of the fluid- the physics of hydraulic brakes! The physics here is great- but the biology is questionable: it's not clear why an octopus would need mask and snorkel!