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Magneview Flim

Get some magnetic viewing film here: 
From Educational Innovations: BUY NOW Magnetic Viewing Film 

Magneview Flim: making the invisible visible and revealing the hidden physics of our everyday world. Microscopic cavities in this green film are filled with oil and tiny flakes of Nickel metal- like compass needles, the flakes align with the magnetic fields revealing the complexity of the north and south pole domains of these magnets. Two of the disk magnets have multiple north and south poles and look like gears with teeth- these are rotors from small motors. 

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


STORY Clock

This very high-tech clock is also high end (more expensive than most items I feature), with excellent craftmaship and technology that is clearly hard to replicate so that it is only made by, and available from, the FLYTE team:

From Art of Play: BUY NOW: Story Clock

From FLYTE: BUY NOW: US & Global Sales Story Clock or in EU Story Clock

STORY Clock: a spherical magnet hovers one centimeter from the face of this amazing clock and orbits in a circle to indicate the time- for this video I selected an orbit period of 40 seconds to show off the motion. The orbit of the magnetic ball can be set to any period but also has default selectable presets to indicate the current hour, minute, or second. This kind of levitation uses 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. Amazing magnetic levitation physics demonstrated by clever engineering by the @flyte.se team, this clock will work lying flat or hung on a wall vertically!

Chaotic magnetic Pendulum

These chaotic pendula are still available on eBay!

From eBay: BUY NOW: Krazy Leg Pendulum

Chick here for similar chaotic systems

Chaotic Magnet Pendulum: adding magnetic forces to gravity gives this pendulum chaotic motion- not random, but very sensitive to slight differences in initial launch conditions. Swipe to see a particular launch path that begins with a semi-stable orbit but then goes chaotic, captured with an attached LED and recorded with a slow shutter app. Arranging the dipoles magnets on the base leads to different patterns of motion- here white attracts and black repels. This vintage device is from the 1970s and was sold by the name “Krazy Leg” by Rathcon Inc.

TrueBalance

Get the full version (8 disks made of wood) or the mini (6 disks, blue or red plastic): 
From Amazon: BUY NOW TrueBalance Coordination Puzzle 

TrueBalance: coordination challenge puzzle- get the six disks, connected by bearing swivels, into a vertical stack by only tilting the handle. Harder than it looks to get each disk’s center of mass above the one below at the same time into the unstable equilibrium final state. The swivels constrain the system, limiting the degrees of freedom, and allowing strange and interesting motion. Kinetic art as a toy! 


Oil Drop Timer

Available here: 
From Amazon: BUY NOW Drop Timer 

Oil Drop Timer: immiscible liquids (colored oil in kerosine) in two connected containers. The oil in each container falls through a small drop forming hole in between clear walls of acrylic. Note how surface tension forms the smaller drops into nearly perfect circles and limits the size of the drop formation. In addition the drops fall at terminal velocity with smaller drops falling faster than larger ones. Repost of one of my favorite inexpensive physics toys.

Tesla's Egg of Columbus

Get this amazing (and affordable) reproduction here:
From engineDIY: BUY NOW: Tesla's Egg of Columbus
This version comes with a 35mm solid aluminum sphere. 

Get the aluminum phiTOP "egg"  here: BUY NOW phiTOP 

Tesla’s Egg of Columbus: an aluminum ellipsoid egg (PhiTOP) mysteriously spins and stands upright in this modern version of Tesla’s famous demonstration from the 1893 World’s Fair in Chicago that first showcased the principles behind wireless power transfer and his AC induction motor. The base has no moving parts- instead special copper windings (very similar to Tesla’s original design) form four electromagnet coils on a circular steel core, and a special circuit supplies each with AC currents in such a way that a rotating magnetic field is created. This rotating magnetic field from the coils under the concave glass induces electric eddy currents to flow in the aluminum ellipsoid- these currents then create their own magnetic field which oppose the initial fields underneath and pushes the ellipsoid to spin. Finally, the ellipsoid top stands up vertically (when spun with sufficient rotational velocity) due to physics similar to that of the tippe-top. 

 

 


Emission Spectra Gases on Radial Mount

I made the display holder and I got this set of gas tubes here (about $9 per tube): 
From Luciteria: BUY NOW: Gas Pure Element Samples 

From engineDIY: BUY NOW: Mini Tesla Coil
For the price, this is the best one on the market- and beautiful to look at in copper- and it comes with three accessories for the top. Please be sure to employ all appropriate safety precautions when utilizing any electrical circuity!

The mount is made by driling holes in this acrylic tube: 4" Acrylic Tube

The breakdown voltages of the elements featured in this post are described by Paschen's Law: 
 
Here is a excellent article with an overview of the physics of glow discharge and its application in lighting and other technologies. 

Click this link to see the mini Tesla coil in action

Emission Spectra Gas Samples: pure samples of hydrogen, nitrogen and five noble gasses are subjected to the high frequency pulsed field of a miniature Tesla coil. Each gas has a characteristic breakdown voltage and emission spectrum- note that Nitrogen has the highest breakdown voltage and begins to glow after the presence of my hand temporarily lowers the resistance to current flow for that tube. The color of each gas is due to a mix of the colors emitted from electron energy transitions specific to each element- the basis of spectroscopy. Notice also that the purple color of the brush discharge at the top of the Tesla coil matches closely to the color of the nitrogen sample, which makes sense as air is 78% nitrogen. 

Happy/Sad Spheres

Get a set here: 

From Educational Innovations: BUY NOW: Happy/Sad Balls

Happy/Sad Spheres: one ball bounces the other stops dead. The bouncy ball is made of neoprene rubber and exhibits high elasticity. The "sad" ball is made of polynorbornene and converts almost all kinetic energy into heat and sound- approximating/demonstrating the case of a completely inelastic collision. Polynorbrene is used in vehicle bumpers, for soundproofing, vibration damping, and other applications where recoil motion is unwanted.

Spherical Dice

A must for any die/dice collectors: 
From Amazon: BUY NOW Spherical Dice 

From eBay: BUY NOW Spherical Dice 

Click this link for other amazing dice featured on @physicsfun 

Spherical Dice: these fair six "sided" dice are hollow inside with a ball that weights each sphere such that one of the six values is always on top. When these dice are rolled (literally!) the internal weight lands in one of six cavities inside creating a low center of mass which aligns one of the numbers to the top. Another low center of mass toy! 


Superellipsoid

Vintage Super Eggs of Piet Hein can be found on eBay: 
From eBay: BUY NOW 
Superellipsoid by Piet Hein 


Get one in brass from this shop: 
From Etsy: BUY NOW 
Brass Super Egg 

Superellipsoid: the "super egg" is a mathematical creation of Danish scientist and artist Piet Hein (also the inventor of the Soma cube puzzle). The equation of the superellipse is that of a regular ellipse, but raising both sides to the power of 2.5 instead of 2- the resulting curve had a flattened end that allows the superellipsoid to stand upright. The superelljpse has found use in architecture and design. This super egg is made of stainless steel.

Balance Stacking Sculpture

Another wonderful desing by BinDesign- get one here in black or natural wood:

From Etsy: BUY NOW: Bin Design Balancer Puzzle

Balance Stacking Sculpture: a series of torques in unstable equilibrium complete this Calder-esque structure. As each component is added its weighted end balances all the others before it, with the initial small piece weighing about a gram or so. Remove the end piece and the whole structure comes down. Another wonderful design by artist Bin Xu.


Lissajous Roller 

Available from Pyrigan & Co.

From Etsy: BUY NOW: Lissajous Roller Illusion

Lissajous Roller: when viewing this 3D printed object from the side one sees a projection of a 3:2 Lissajous curve, but the object is actually cylindrical in frame and can roll towards or away from the viewer. When in motion a “dual axis illusion” is produced where the object appears to be rotating about a vertical axis. Invented by Bill Gosper and produced by Pyrigan & Co. 

Neon Plasma Glass

Each glass is unique and comes with tesla coil base:

From Etsy: BUY NOW: Neon Glow Glass by TeslaCoilPro

Neon Plasma Glass: these double walled glass mugs glow orange and blue from the excitation spectrum of neon gas at low pressure. The base contains a high frequency transformer (Tesla coil) that generates high voltage electric fields (but at very low current) from USB rechargeable batteries- which excites the neon to glow, and also serves as a coaster. The inner volume varies in thickness which leads to variations in heat and pressure which in turn produces different excitations (orange and blue) of the neon gas in patterns that dance and dazzle the eye. Stunningly beautiful kinetic art and tech by creator Zerg Dragonymous.

TV Rock

Get samples of Satin Spar here 
From eBay: BUY NOW TV Rock: Satin Spar 

Get samples of Ulexite here 
From eBay: BUY NOW TV Rock: Ulexite 

TV Rock: special crystalline form of the mineral gypsum acts as a natural fiber optic image conduit. Morocco seems to be the main source of this fibrous form, called satin spar gypsum, which exhibits pearl like luster and chatoyancy along two axes and transparency along the direction of the fibers. Not to be confused with ulexite, a mineral of boron with similar TV rock properties.