Floating Yen
Aluminium 1 Yen coins are the perfect denisty to float as shown in the video:
From Etsy: BUY NOW: 1-Yen Coins
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Floating Yen: the surface tension of water is strong enough to suspend the aluminum coin, and a trapped column of air in a second glass can submerge a portion of the surface with the coin. The 1-Yen coin has just the right mass and density for this demonstration. One of my favorite DIY physics demonstrations.
Magic Portal Illusion
Get a portal illuison here:
From Etsy: BUY NOW: Magic Portal Illusion Desk Toy
Or print it yourself: 3D Print Files: Magic Portal Desk Toy
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Magic Portal Illusion Version 4: the latest update of this new astonishing illusion, now with three separately moving colorful strands that seem to pass in and out of a 4th dimension. The mechanical principle employed is similar to that of a lead screw and slider type actuator, except here translating the slider up and down rotates the helical strands at just the right rate to produce the illusion. Another in a series of amazing 3D print creations by Ada Cohen.
Levitating Cube Tensegrity
Get the 3D print files here: Levitating Cubes
Similar fun tensegrity prints often available on Etsy
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Levitating Cube Tensegrity: connected only by four segments of fishing line! An amazing 3D print creation by @heliox_lab where the beautifully symmetric configuration is stable in all orientations. Another fun take on the tensegrity concept, invented by Kenneth Snelson and made famous by the architect Buckminster Fuller in 1949.
Camphor Propulsion Boat
These vintage Champhor Craft boats are hard to find. Here is a camphor propelled toy still being made:
From eBay: BUY NOW: Camphor Craft Boats
Camphor Craft Miniature Self Propelling Toy Sailing Ship: this vintage toy boat is propelled by a difference in surface tension. Fluids will flow away from regions of lower surface tension (Marangoni Effect) and as the camphor mixes with the water at the stern of the boat a gradient of surface tension is created pushing the boat forward. Made in Cornwall England-swipe to see this 1960’s vintage toy in its original packaging.
Ray Optics Tabletop Kit
Get this inexpensive but functional and fun kit here:
From Amazon: BUY NOW: Laser Ray Optics Kit
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Ray Optics Tabletop Kit: explore how lenses work with this inexpensive experimentation kit featuring three parallel laser beams and 2-D versions of lenses and other shapes that use refraction to alter the direction of light. Here a doubly concave lens interacts with the beams from a doubly convex lens.
Coupled Oscillators
Similar devices available from this previous posting: Kinetic Wave Wires
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Coupled Oscillators: two identical leaf springs with attached magnets oriented to repel. When the mass configuration on each spring is equivalent, the two springs will have the same natural (resonance) frequency and the energy will then make a complete transfer back and forth, with each spring taking a turn standing still.
Curie Point Heat Engine
This DIY project is pretty easy to build. One half of one of these inexpensive magnetic necklace clasps will work well for the heated magnet.
From Amazon: BUY NOW: magnets for curie point engine
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Curie Point Heat Engine: when the magnet on the end of the wire heats up to a particular temperature (the Curie point) its magnetic field is temporarily lost until it cools. This engine design uses a second magnet to pull the swinging magnet back into the heat source once the magnetic field is reestablished. Repetition of this process creates mechanical motion as long as the heat source is fueled.
Lenz's Law: Copper v Aluminum
Finding copper and aluminum tubes of the same dimansions can be tricky. Here is a starter set with a copper tube:
From Amazon: BUY NOW: Lenz's Law Demonstration Kit
From Amazon: BUY NOW: Magnetic Viewing Film
See my other posts on the Feel Flux devices
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Lens’s Law Copper v. Aluminum: two tubes, identical in diameter and wall thickness, allow direct comparison of the conductivity of these metals. Al is only about 60% as conductive as Cu, so a 10 inch long pipe of Aluminum is expected to have the same effect as a 6 inch copper pipe. If two identical magnets are released at the same instant with these lengths we expect the magnets to emerge from the bottom of the tubes at the same time (petty close as seen in slow motion). Magnaview film reveals that the magnet does indeed move proportionately slower in the copper tube due to the larger eddy currents generated. I obtained this set from teachersource.com a few years ago.
Animallusions Zebra
The original DIY dragon from G4G 3: Dragon.pdf
Animallusions Zebra: an amazing version of the hollow face illusion where the zebra’s head appears animated, and gives the impression that it’s always looking in the direction of the viewer. This zebra seems inspired by the dragon illusion created for the 1998 Gathering for Gardner by the Binary Arts Corporation of Bill Ritchie et al. Some fun physics of perspective and psychophysics for your shelf.
Lenz's Law Loops Demonstration
Get this affordable device here:
From Amazon: BUY NOW: Lenz's Law Balanced Loops
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Lenz’s Law Loops Demonstration: a strand of aluminum, curled into a loop at each end, is balanced on a rotation point. A strong neodymium magnet at the end of a rod can interact and manipulate the balanced structure without touching it. Note that the closed loop allows a current to form and flow completely around the loop, whereas the loop with a gap barely interacts. A changing magnetic field (from the point of view of the moving loop) induces an electric current in the loop, which in turn produce an electromagnetic field (but of lesser strength) with opposing polarity. A fun demonstration to explore the foundational concepts of Faraday and Lenz.
Single Strand Tensegrity
Get the 3D print files here:
From Thingverse: Make Now: Single String Tensegrity
Click here for more tengerity in my collection.
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Single Strand Tensegrity: a vertical chain- when held under tension a single length of thin chain can become a rigid support structure. In this design four 3D-printed struts each act like an archer’s bow to stretch the chain under tension. Beads placed on the chain interlock with the ends of the struts. Design and .stl files by Ernie Condone and printed by Roger Key (thanks!)
Projection Kaleidoscope
Get this fun DIY kit here:
From eBay: BUY NOW: Projector Kaleidoscope Kit
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Projector Kaleidoscope: mirrors, symmetry, and the physics of optics are all explored through the assembly of this unique projector kaleidoscope project. Invented by the famous Scottish physicist Sir David Brewster (1781-1868), the kaleidoscope is one of the most popular physics toys ever sold.
Silicon Integrated Circuit Wafer
Similar affordable wafer samples available here:
From Amazon: BUY NOW: Silicon Wafer
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Silicon Integrated Circuit Wafer: this shiny disk comes from an intermediate step in the production of electronic microcircuits and serves as a reminder of the astonishing technological achievements of semiconductor physics. The disk itself is a polished slice of lab grown nearly defect free 99.9999999% pure silicon crystal. Upon this particular disk is an array of more than 11000 rectangular integrated circuits that in the next step would be diced and placed into a pinned package for installation onto a circuit board. Within each 1mm wide rectangle is a collection of hundreds of circuit components such as transistors, resistors, capacitors, all interconnected via conductive channels and created through a myriad of processes including photolithography, acid etching, ion implantation, and thin film deposition to create 3D structures at this microscopic scale. This wafer was tested defective and made available for educational purposes, showcasing how physics is at the core of our daily use of technology.
Reversible PEM Fuel Cell
This kit includes the fun gas collection cylynders and all compnents needed:
From Amazon: BUY NOW: Horizon PEM Fuel Cell kit
Affordable PEM fuel cells are available here:
From Amazon: BUY NOW: PEM Fuel Cells
The physics and chemisty are complex (with cool microsope images of a membrane): Wikipedia on PEMs
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Reversible PEM Fuel Cell: this blue unit contains a Proton Exchange Membrane and platinum catalyst that enables an electrochemical reaction to generate electricity from combining hydrogen and oxygen into water (a hydrogen fuel cell), and if a current is supplied (say with two AA batteries) the process runs in reverse with the PEM assembly converting water in to hydrogen and oxygen (one side delivers O2 the other H2). This kit uses little “diving bell” structures to capture the gasses that can then be used as fuel to power a motor. Note that the amount of hydrogen produced is exactly twice that of oxygen- reflecting the composition of water H2O! The fabrication of PEMs is a complex process at the forefront of physics and chemistry under refinement since the 1960s. Note the amazing dual use of PEMs, as a source of electrical energy when supplied hydrogen, or as a means to store energy in the form of hydrogen.
Assassin's Water Bottle
Get this water bottle (and accessories) here:
From InqFactory: BUY NOW: Assassin's Water Bottle
See Steve's excellent video on the Assasin's Teapot
Get the working teapot replica here:
From Amazon: BUY NOW: Assassin's Teapot
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Assassin’s Water Bottle: a very modern take on the ceramic assassin’s teapot novelty vessel that harbors a hidden chamber and can clandestinely dispense two different liquids. Similar to the teapot, covering one of two small holes of this bottle limits access to atmospheric pressure and determines from which chamber liquid is poured (in this case red or blue Powerade). This modern version is the brainchild of my friends @stevemouldscience and @electricpants and features as a logo the two states of Schrödinger’s cat- and also comes with insulating covers to hide the chambers (if desired).
Shadow Stereographic Projection
These mathematical art objects are created by Henry Segerman and the print files are available here:
From Thingverse: Download NOW Mathematical Art
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Wikipedia has a nice introduction to the math and applications of stereographic projection.
Shadow Stereographic Projection: 3D printed sculptures that cast geometric shadows. When illuminated by a point source of light (placed at the top pole of the sphere) the shadow cast by the rays of light represent a one to one mapping of the points on the sphere to points on the plane- creating a square grid, and a honeycomb of regular hexagons. Stereographic projection is often used in representing the geography of the globe of our planet on to a flat map. Mathematical art by Henry Segerman.
Heterodyne Bat Detector
This exect model availble here:
From ebay: BUY NOW: Bat Detector
More expensive models here:
From Amazon: BUY NOW: Bat Detector
and an inexpensive kit here: Bat Detector Kit
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Heterodyne Bat Detector: when bats are out hunting they emit echolocation chirps that fill the air with sound we can’t hear. Using a special microphone this device receives the inaudible 25kHz-100kHz acoustic emissions of these flying mammals and mixes them with a generated frequency to produce beat frequencies below 17kHz that humans can hear (signal processing of a heterodyne). Different bat species produce different frequency echolocation chirps and a knob on the device allows selection of the generated frequency to select out what signals are in the air that evening.
Electric Motor Build
Get an easy to assemble kit here:
From Amazon: BUY NOW Simplest Motor Kit
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Electric Motor Build: One of the most important inventions consists of only three basic components as shown here: coil, magnet, and a battery with lead wire posts. The wire of the spinning coil has an insulating coating on it- and this coating is carefully scrapped off one side of the thin wire on each end. When current passes through the coil it becomes an electromagnet and the permanent magnet repels it making it spin- as it turns the current goes on and off depending on if the copper wire posts are in contact with the bare wire side (current on) or the part of the wire with the insulating coating intact (current off). When the current is off momentum keeps the rotation going until the next push. The physics of converting electric energy to rotational kinetic energy- and a fun DIY project!