From Amazon: BUY NOW Andrus Tri-Zonal Space Warper
From eBay: BUY NOW Tri-Zonal Space Warper
Magician and professor of psychology Richard Wiseman describes the genius of Jerry Andrus and the psychophysics of the Space Warper.
Andris Tri-Zonal Space Warper: Stare at the center of the spirals for at least 15 seconds- the next thing you look at will appear to be in motion. This spinning disk top features the famous illusion by magician Jerry Andrus that demonstrates aspects of the physics and psychophysics of our visual perception- specifically the part of our brain that detects motion. The effect is even stronger in person than in the video.
Wikipedia has this introduction to the phenomena of the Aircraft Glory
For a detailed discussion with math, see this entry from the Physics Stack Exchange
Airplane Glory: optical phenomenon that forms rings of color in the clouds- in this case around the shadow of my 737 flight, and is not the same physical process as that of a rainbow. Airplane glories are produce only by very tiny droplets (tens of visible light wavelengths across) in the cloud, and arise due to complex process called wave tunneling, where the electromagnetic waves that make the colors are induced in the drop by a photon only passing close by its surface. Interestingly, the exact details of this phenomenon is still an active area of research! Caught this out the window returning yesterday from a national science teachers convention in Atlanta.
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.
This image by István Orosz is available as a poster and as a puzzle:
From Amazon: BUY NOW Mysterious Island Puzzle
From MathArtFun.com: BUY NOW Mysterious Island Poster
For those who want to see the math behind this art, here is an initial paper on the topic published in 2000 in the American Journal of Physics: Anamorphic Images by Hunt et al.
Many books are available (with mirror cylinders) from Amazon: Anamorphic Art in Books
Mirror Anamorphosis: this famous print by artist István Orosz has a hidden anamorphic image revealed by placing a mirrored cylinder over the depiction of the moon in the image. The work visualizes a scene from the book “The Mysterious Island” by the science-fiction author Jules Verne- whose portrait emerges in the reflection on the cylinder. The math describing this mapping is quite complex and was given in detail in a physics journal in 2000, but before that Martin Gardner described the math in 1975. Repost for this week’s theme as I head to G4G!
Get a set here:
From Amazon: BUY NOW Balance Cups
Balance Drinking Vessel: physics meets design in this stainless steel cup- when empty the cup tilts to one side, but when full it stands straight. The walls of this spherical vessel are hollow, asymmetric, and weighted, designed with the center of mass displaced from the symmetry axis such that the empty cup rests in stable equilibrium at a 23 degree tilt. The addition of mass (pouring a drink) within the offset interior of the cup places the center of mass (cup + contents) onto the symmetry axis allowing an upright stable equilibrium. Designed by Katja Hoeltermann for Carl Mertens design of Solingen Germany.
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!
The hoop used is just the inner circle of an embroidery hoop. Get one for a couple dollars here:
From Amazon: BUY NOW Wooden Hoop
The science writer Martin Gardner has published many books of physics tricks and simple but amazing science experiments like the one in this video. Highly recommended.
From Amazon: BUY NOW Martin Gardner's Science Magic: Tricks and Puzzles
Bottle, Hoop, and Nail Trick: with some practice, a snap of the wrist removes the hoop and the nail falls straight into the bottle. Newton's 1st Law as seen in slow motion- a mass at rest tends to stay at rest. (Best to watch with sound/audio) Balancing the nail on the hoop ensures the nail is directly over the top of the bottle. The hoop is removed so quickly that it does not interact significantly with the sufficiently massive nail, and thus the nail remains over the mouth of the bottle so that gravity pulls it in. G4G Week repost- a favorite from Martin Gardner’s collections of physics tricks.
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.
Available from this famous science supplier in Japan:
From Narika: Foucault Spring Pendulum
Wikipedia has a nice description of the physics and applications of the Foucault Pendulumincluding this spring version.
Foucault Oscillator: like a swinging pendulum, the motion of a mass on the end of a straight wire spring is constrained to a plane. The container is moved around yet the orientation of the oscillating mass points in the same direction. Similar to the physics behind the famous Foucault Pendulum that keeps its orientation as the Earth moves underneath.
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.
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.