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Euler's Disk

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From Amazon: BUY NOW Euler's Disk 

Wikipedia has an excellent introduction to the physics of Euler's Disk 

Eulers Disk: (best with sound on) this toy exhibits the motion of a “sprolling” coin, a motion that combines spinning and rolling. Designed with a large mass and very smooth edge, this device takes close to 3 minutes to come to rest- and amazingly, the contact point between the disk and the mirror can reach a speed of more that 200 mph! This video catches the first and last parts of this 2 minute and 42 second run, with two cuts to 240fps slow motion to show the curious motion. Watch the end with the sound on! 

Rolling Ball Fountain

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Rolling Ball Fountain: this miniature kugel fountain features a glass sphere that sits on a socket of precisely similar shape, and is suspended on a very thin (less than half a mm) film of moving water which greatly reduces friction. The velocity of the water in the thin layer slows as it spreads out via a hole in the socket, and this hole is offset from the center so that the interaction with the water stream sets the ball spinning. A small pump provides the flow rate, and colorful LEDs illuminate the glass sphere to show off the rotation. Perhaps you’ve seen public art installations featuring giant granite spheres weighing tons and yet similarly suspended on a thin layer of flowing water. Physics principles involved here include viscosity and Reynold’s number, the Navier-Stokes equation, Bernoulli’s principle and the study of thin layer lubricants.

Zoetrope

Get this inexpensive version here- comes with many animations and balnk strips tomake your own:

From Amazon: BUY NOW: Zoetrope 

Zoetrope: the physics and psychophysics of motion animation- still images flashed in rapid succession produces the illusion of motion through persistence of vision. The slits are crucial to creating the illusion by blacking out the visual stimulus for a short duration- without these pauses only a blur is perceived. When the image flash rate is above the flicker fusion frequency (approximately 16Hz) we perceive fluid motion- the basis for all movies and TV. 


Hyperbolic Holes

This inexpensive kit available here: From Amazon : BUY NOW
Hyperbolic Holes Kit

Hyperbolic Holes: a straight rod, in this case a pencil, glides through a symmetrical pair of curved holes. The design is based on the hyperboloid, the 3D ruled surface traced by an offset rotating diagonal line. This device is sold as an inexpensive kit to assemble yourself, and includes a motor with geared drive and pre-cut pieces. The pencil is my addition- just the right size to clear the curved openings.

Backflipping Wind-Up

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from Amazon: BUY NOW: Backflipping Wind Up Toys

Backflipping Wind Up: an energy transfer toy- a wound coil spring transfers and stores energy through a set of gears to a straight spring which is suddenly released to create kinetic energy which is then converted to gravitational potential energy- sending the toy air bound into a back flip. Here the Uglydoll character Is made of clear plastic allowing the internal mechanism to be visible. In addition the feet of the character must push off with just the right rotation rate to allow for one full rotation in the air, and the tail has a foam pad to absorb the impact and stop the rotation. A lot of fun physics to consider in this toy.


Vertical Mendocino Motor

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Vertical Mendocino Motor: each face of solar cell is connected to a coil of copper wire. Spins fast and quite in a sunny window. As the rotor turns each solar cell takes a turn in the brightest light, which provides electric current to one of the coils which becomes a temporary electromagnet that pushes against the permanent magnet configuration in the center- propelling the rotor to rotate. The rotor assembly is nicely symmetric and balances on a sharp point for minimal friction. Invented in the 1960s by Daryl Chapin of Bell Labs and popularized by Larry Springs of Mendocino CA 


Magnetic Sand Hourglass

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From Amazon: BUY NOW Magnetic Hourglass

From Amazon: BUY NOW Magnetic Hourglass

Magnetic Sand Hourglass: ferromagnetic sand collects above a neodymium magnet in the wood base. Each particulate of ferromagnetic iron becomes a temporary dipole magnet in the presence of the magnetic field in the base. The tiny dipoles link up north ends to south ends, creating interesting patterns that reveal the magnetic field lines. 

Infinity Mirror Lamp

Also sold as a lightbulb: 
From Amazon: BUY NOW Infinity Mirror Firework Bulb 

Infinity Mirror Lamp: illusion of depth from multiple refections. This glass bulb sphere is partially coated inside and out with a thin metal layer. The metal layer is made thinner in a pattern of small circles to produce iridescent colors through thin-film interference effects. When lit from within by white LEDs, multiple reflections on the curved contour create the firework like spray of light and color. So much physics going on in this inexpensive novelty lamp!


Kinetic Sandscape

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Kinetic Sandscape 

Kinetic Sandscape: the phenomenon of spontaneous stratification is a striking feature of this sand motion desk toy. Typically pouring stuff together results in further mixing, yet here, when the sand mixture descends through a gap in the air bubbles, the resulting pile is ordered into sorted layers. The larger rounded dark grains separate from the smaller sharp-edged white grains forming the layers you see here. The darker grains alone would stack into a steeper pile (larger angle of repose) than the white which would form a less steep pile. The stratification process is a slow one in this device, here about 30 minutes have been condensed to the 60 second IG format. 

Micro Racer in a Glass

These micro racer cars are sold under many brand names, and most come with a clear sphere to demonstrate this centipetal accelration phyenomenon. 

From Amazon: BUY NOW: Micro Racer + Sphere

Micro Racer in a Glass: This tiny battery powered car overcomes gravity through centripetal acceleration and slight friction with the glass surface. With sufficient velocity the surface normal force supplies the centripetal acceleration. The car’s battery last for many minutes and is USB rechargeable.


Revolution

This vintage toy can sometimes be found on eBay. 
Quality models of the New version of this physics toy are still available  
From Amazon: BUY NOW Magnetic Levitator 

Revolution: vintage 2D magnetic levitation- permanent magnets can only produce static equilibrium along two dimensions- here a glass mirror constrains the third dimension, and makes for a nice bearing surface for rotation. This item was sold in the 1990s in mall shops such as Natural Wonders. 

Mendocino Motor

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From Amazon: BUY NOW Solar Levitating Motor 

Mendocino Motor: each face of solar cell 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 

Thermochromic Beam Down Mug

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From Amazon: BUY NOW Beam Down Star Trek Mug (Customized)

Thermochromic Beam Down Mug: Pour up some hot coffee and watch the crew of the USS Enterprise leave the ship and rematerialize on the planet surface with this color-changing physics mug. The color change employs leuco dyes, thermochromic chemicals that have two reversible forms, one colorless.