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Physics Toy Store 10



Tesla's Egg of Columbus: Copper PhiTOP version

Tesla’s Egg of Columbus: a copper 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. Rotating magnetic fields from under the wooden platform induce electric eddy currents to flow in the copper PhiTOP- these currents then create their own magnetic field which oppose the initial fields underneath and pushes the PhiTOP to spin. This version differs from Tesla’s in that the rotating magnetic fields are created by, well, a pair of rotating neodymium magnets (revealed by lifting the top platform in this model). Credit to astrophysicist Kenneth Brecher, the creator of the PhiTOP, and this unique means of using a common lab magnetic stirrer to create the induced currents. Finally, the ellipsoid top stands up vertically (when spun with sufficient rotational velocity) due to physics similar to that of the tippe-top. ➡️ Follow the link in my profile for info on where to get a PhiTOP and other amazing items featured here on @physicsfun #ellipsoid #oblateellipsoid #conicsections #tippetop #torque #angularmomentum #lenzslaw #magneticstirrer #magneticinduction #tesla #teslasegg #ACMotor #eggofColumbus #rotationalinertia #PhiTOP #physics #physicstoy #flip #flipover #precession #spin #spinning #top #spinningtop #science #scienceisawesome

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PhiTOPs are available in Aluminum, Brass, and Copper (most conductive!):

From Etsy: BUY NOW PhiTOP in Copper
From Etsy: BUY NOW PhiTOP in Brass
From EI: BUY NOW PhiTOP in Aluminum

See the videos below for more on the PhiTOP and using magnetic induction to spin it up.


Induced Current Spin-Up: PhiTOP on a magnetic stirrer

Induced Current Spin-Up: Spinning magnets from the magnetic stirrer induce electric currents to flow in the brass PhiTOP- these currents then create their own magnetic field which opposes the magnets underneath and pushes the PhiTOP to spin. Credit to astrophysicist Kenneth Brecher, the creator of the PhiTOP and this unique means of using Lenz’s Law to spin it up. This top stands up vertically (when spun with sufficient rotational velocity) due to physics similar to that of the tippe-top. The concave lens keeps the top from wandering off of magnetic stirrer. ➡️ Follow the link in my profile for info on where to get this device and many other amazing items featured here on @physicsfun #ellipsoid #oblateellipsoid #conicsections #tippetop #torque #angularmomentum #lenzslaw #magneticstirrer #magneticinduction #tesla #rotationalinertia #PhiTOP #physics #physicstoy #flip #flipover #precession #spin #spinning #top #spinningtop #science #scienceisawesome

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This inexpensive lab stirrer (which I modified to have a transparent top) can be used in many investigations and demonstrations:

From Amazon: BUY NOW Magnetic Stirrer
See the links below for info on where to buy a PhiTOP (Aluminum or Brass versions)- both come with a concave mirror.


The ΦTop - Golden Version

The ΦTop - Golden Version: spinning things have surprising physics! This unique top is made of solid brass in the shape of a prolate elIipsoid- and the name of the top is derived from the following design requirement: the ratio of the semi minor (short) axis to the semi major (long) axis is made equal to the mathematical constant the golden ratio φ (phi). Invented by astrophysicist Kenneth Brecher, this top stands up vertically (when spun with sufficient rotational velocity) due to physics similar to that of the tippe-top. The concave mirror keeps the top from wandering off and the glass surface has minimal friction allowing the top to spin for a long time- this video shows various stages of 8 minutes of total spin time. ➡️ Follow the link in my profile for info on where to get this top and many other amazing items featured here on @physicsfun #ellipsoid #oblateellipsoid #conicsections #tippetop #torque #angularmomentum #rotationalinertia #PhiTOP #physics #physicstoy #flip #flipover #precession #spin #spinning #top #spinningtop #science #scienceisawesome

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This version of the ΦTop is made of solid brass and has a mass more than three times that of the aluminium version (see photo below), the difference in weight is substantial and obvious when handling these tops. The brass version will spin much longer due to its larger inertia.

Professor Brecher has a limited supply of these "golden" (brass) versions of this top available on Etsy

From Etsy: BUY NOW PhiTOP in Brass

See the video below for the aluminum version.


PhiTOP

The PhiTop: spinning things often have surprising physics! This unique top is made of solid aluminum in the shape of a prolate elIipsoid- and the name of the top is derived from the following design requirement: the ratio of the semi minor (short) axis to the semi major (long) axis is made equal to the mathematical constant the golden ratio φ (phi). Invented by astrophysicist Kenneth Brecher, this top stands up vertically (when spun with sufficient rotational velocity) due to physics similar to that of the tippy-top. ➡️ Follow the link in my profile for info on where to get this and other amazing items featured here on @physicsfun #ellipsoid #oblateellipsoid #conicsections #tippetop #torque #angularmomentum #rotationalinertia #physics #physicstoy #flip #flipover #precession #spin #spinning #top #spinningtop #science #scienceisawesome

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Get one here!


From Educational Innovations: BUY NOW PhiTOP
From Amazon: BUY NOW PhiTOP



Computational Caustics Image Projection

Computational Caustic Projection: an image is formed by refraction through a free form lens in a new process that utilizes the physics behind how light is concentrated into caustics. This piece of molded acrylic has a surface of slight but precisely constructed curves, that when lighted by a broadband light source (Maglite flashlight bulb), projects an image of a lion onto a plane. This is not a hologram, but instead a new proprietary light redirection technology by the company RAYFORM. 🌟 Special thanks to RAYFORM technologies for sending me this sample. ➡️ Follow the link in my profile for more info and where to find many of the amazing items featured here on @physicsfun #physics #physicstoy #physicsfun #optics #rayform #lens #caustics #refraction #lightrays #kineticart #computationcaustics #rayformtechnologies #science #scienceisawesome

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RAYFORM is a start up company developing this new technology based on the physics of caustics formation described here: RAYFORM technologies






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