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Butterfly Mendocino Motor

Get this elegant motor here:

From Etsy: BUY NOW: Butterfly Medocino Motor

Butterfly Mendocino Motor: the simplest (and very elegant) version of this motor with only two photovoltaic cells mounted with care to ensure precision balance. This motor will spin quietly to high RPMs on any sunlit windowsill. In this model made by Semyon Nazarov of SolarWindRU, each of the two photovoltaic solar cells is connected to a coil of copper wire under the opposing solar cell. When the rotor is lit from above the top solar cell provides electric current to the coil in the bottom position which becomes a temporary electromagnet that pushes against the permanent magnet in the base propelling the rotor to rotate. As the rotor turns, the coil that moves into the bottom position is likewise energized by the solar cell currently at the top- one can say the light commutates this motor. 2D magnetic levitation is provided by permanent magnets where an acrylic plate constrains the third dimension, and makes for a nice bearing surface for minimal friction. Invented in the 1960s by Daryl Chapin of Bell Labs and popularized by Larry Springs of Mendocino CA

Lava Lightning Lamp

Similar itmes available here: 
From eBay: BUY NOW: Lighting Plasma Lamps

Lava Lightning Lamp: low pressure noble gasses glow due to discharge from high voltage and stimulate colored phosphors to emit yellow, blue, and red in this vintage device by Lava. A small high frequency coil at center creates the high voltage potential between the center electrode and the outer glass casing which is coated with a thin transparent film of metal. Current flow through the thin gas produces the glowing zigzagged path like that of lightning but more rounded. Shown here in 480 fps slow motion. Another of my vintage plasma lamps in my collection. 

Simple Stirling Engine

Get this amazing model engine here:

From EngineDIY: BUY NOW: Simple Stilring Engine

See other featured DYI devices here: EngineDIY Models

Simple Stirling Engine: Perhaps the simplest piston engine ever devised- a single piston powered by a tiny alcohol lamp. Glass components allow a view of the internal workings of this design, and the interesting startup behavior from oscillation to full rotation. Heat engines produce mechanical motion from a difference in temperature- here the piston side is near room temperature (the central aluminum post is an excellent conductor and acts as a heat sink as the gas flows through), and the test tube is kept at high temperature via the flame, with metal fibers to help conduct the heat into the air (this component is called the regenerator). Swipe to see the elegant assembly of this model, and swipe again to see the engine power down. This external combustion design is attributed to Scottish engineer Robert Stirling back in 1816.

The PhoTOP

Get a PhoTOP from these fine vendors (comes with laser pointer!):

From Educational Innovations: BUY NOW PhoTOP 
From Vat19: BUY NOW: PhoTOP

Another amazing spinning device by Prof. Ken Brecher! Get his other spinning tops here:
From Etsy: BUY NOW: PhiTOP, PiTOP, eTOP, iTOP, DeltaCELT

The PhoTOP: phosphorescent glow illuminates the intricate path of a 405nm laser pointer beam on a balanced spinning disk. Let the disk set alone for a few minutes to allow the traces to fade- and repeat again and again to experiment making new patterns.

Half Seirpinski Octahedron Fractal

Get this amazing 3D print here:
From Etsy: BUY NOW: Seirpinski Pyramid

or print it yourself:
From Thingverse: Seirpinski Pyramid

Half Sierpinski Octahedron Fractal: this 3D printed math sculpture is one half of the sixth iteration of what is called “the octahedron flake” a 3D fractal based on the Sierpinski triangle. To make this fractal, on each iteration an inverted triangle is removed from the center of the previous triangle, and if this process is repeated indefinitely one gets the famous fractal. For this 3D print, the maker Travis Quesenberry used rainbow silk PLA to create the beautiful color gradient base on the .stl files by Rick Tu. Another example of math brought to life via 3D printing! 


Advanced Gyro: Hybrid Spinning Top

Get one from David Fowler's shop: 
From PhysicsHack: BUY NOW: Advanced Gyro
Made with extraordinary craftsmanship and high quality materials, and sold at a very reasonable price! 

Hybrid Gyroscope Top: the Advanced Gyro is a new design by @physicshack and in defiance of gravity this gyroscope can hang from a string attached only at one end. No pull cord needed, this unique design spins up via friction with a working surface (thin cardboard works well) and applying a circular motion to bring the rotor up to 1000s of RPM. Machined from solid stainless steel this top weighs in at about half a kilo, providing inertia that produces long spin times. 

In-Feed Google

Pendulum Snake

Get this version here:

From Amazon: BUY NOW: Pendulum Snake

Pendulum Snake: 15 independent swinging pendulums, each with a slightly longer period than the one to its left side, create mesmerizing wave patterns. As the pendulums get further out of phase with each other the waves become shorter and faster. This order and pattern is quickly destroyed if two of the pendulums were to collide (swipe for demonstration).

Andrew's Space Wheel

This vintage 1970s item available now on eBay 
From eBay: BUY NOW Andrews Space Wheel 

Andrew's Space Wheel: kinetic art desk toy from the 70s- the rotor will stay in motion for weeks, until the hidden 9V battery is depleted. The rotor has a magnet at the end of each spoke- a coil and circuit identical to that of the "Top Secret" mystery top that I've posted about gives these magnets a push as the rotor passes through the middle- conservation of energy and angular momentum does the rest! 

Wimshurst Electrostatic Generator

Get this inexpensive version that makes big sparks!

from Engine DIY: BUY NOW: Wimshurst Electrostatic Generator

Wimshurst Electrostatic Generator: this device uses two counter rotating disks of metal pads to separate charge via induction. The repulsion felt by electrons as the triangle plates pass by each other pushes charge to flow across two conducting rods, one on each side, which allows the charge to stack up. This excess charge is then stored in old fashioned cylindrical capacitors (Leyden Jars) until the resulting 30,000+ Volts is achieved to jump the air gap. This device goes back to 1883- invented by James Wimshurst

Gauss Gun

Similar device available here: 
From Amazon: BUY NOW: Gauss Gun

Gauss Gun: acceleration of steel balls through magnetic potential energy and cascading collisions. Four neodymium magnets provide the potential energy that is converted into significant kinetic energy of the end steel ball. The initial configuration has two steel balls on one side of each magnet- an incoming ball on the opposite side accelerates and impacts each magnet in turn sending each loosely connected second ball off with greater speed. 

Cherry Blossom Thermochromic Sake Cups

Similar cups available here- some change with hot water, some with cold:

From Amazon: BUY NOW: Cherry Blossom Color Change Cup

Check out these other thermochomic physics toys

Cherry Blossom Sake Cups: ice cold liquid produces blue blossoms on the initially bare branch, but pour in a hot beverage and the branch fills with pink flowers! The designs at the bottom of these ceramic color-changing cups employ leuco dyes, thermochromic chemicals that have reversible forms, one colorless.

Tesla Coil

For the price, this is the best one on the market I think and beautiful to look at in copper- the music function does not do much, but it is a great little Tesla coil and it comes with three accessories for the top. Please be sure to employ all appropriate safety precautions when utilizing any electrical circuity! 

From engineDIY: BUY NOW: Mini Tesla Coil

Tesla Coil: miniature low current version of the famous air core double-tuned resonate transformer invented by Nikola Tesla in 1891. The thick copper of the primary coil is set into three windings around the many windings of the tall secondary coil. This one uses a modern transistor circuit to excite the radio frequency oscillations that produce a voltage in excess of 50kV in the form of pulses that cycle about 100k times a second. This version is fed by a 24V DC power supply and is fairly safe due to a low current (mA)- but the circuitry does get hot and demands a huge heat sink with fan (the metal base can burn skin when operating). The coils comes with attachments- the spike produces a purple corona discharge as the voltage exceeds the breakdown voltage of air with current flowing into the air or arcing over to a grounded piece of metal. The corona discharge imparts momenta, and here the ends of a bent wire are set into rotation from the slight push of the escaping electrons. Swipe to see the ejected electron stream propel the end of a thin wire into a final state circular orbit. The more interesting behavior occurs during the initial transient orbits which seem to be hypotrochoid type curves beautifully captured here using the Slow Shutter app. 

Dodecahedron Infinity Mirror

This lamp is interesting, but the fabrication is low quality. Still, it is fun to see the internal reflections and it would make for a great party light. Definitely read the reviews before purchasing! ($30-$45 USD) 

From Amazon: Dodecahedron Infinty Lamp

Dodecahedron Infinity Lamp: lit from within by strips of LEDs the 12 plastic mirrored faces create a universe of interesting internal reflections. While the manufacturing quality of this item is pretty low, when the lights are off it looks pretty amazing.


Self-Propelled Homopolar Motor on Aluminum Foil Racetrack

I used neodymium disk magnets, small end = 1/2" diameter, Large end = 3/4" diameter. 
From eBay: BUY NOW Disk Magnets for Simple Motor 

Foil Runner Motor assembly diagram: 
Self-Propelled Homopolar Motor on Aluminum Foil Racetrack: A favorite DIY physics toy where disk shaped neodymium magnets supply the static magnetic field for this motor and become the wheels of a very simple vehicle with an AAA battery as the energy source. As soon as both ends make contact with the conducting aluminium foil an electric current will flow which in turn induces a magnetic field underneath the battery assembly. This induced field will then interact with the neodymium magnets on each end causing them to spin- a wonderful example of a motor with minimal components. The racetrack is a cardboard circle from a pizza box covered in kitchen foil.

Liquid Xenon Ampule

Available here:

From Luciteria Science: BUY NOW: Liquid Xenon Ampule

Liquid Xenon Rapid Phase Change: this small sealed vial contains pure xenon gas at very high pressure- 65 atmospheres! When cooled to 16C (61F) the xenon gas undergoes a rapid phase change to liquid as seen here when the ampule is immersed in an ice water bath. The video is shown in real time and the liquid xenon returns to gas within a few seconds and the process can be repeated indefinitely. The vial is made of fused quartz and kept small (3cm long) to be able to contain the high pressure environment which allows for such a high condensation temp (usually much colder at -108C).