All physicsfun toys

Maxwell’s Dynamical Top

This version of Maxwell's Top was produced in limited quantities in the 1990s by Lee Valley Tools. Currently hard to find. 

See these posts for a detailed replica of Maxwell's Top Appratus

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Similar physics to gyroscopes! Click on this link for many interesting types. 

Maxwell’s Dynamical Top: one of my favorite demonstrations of the strange properties of rotating bodies- this version based on an experiment by the great physicist James Clerk Maxwell. When this massive brass bell shaped top is spinning an interesting stability can occur- push on the stem with an object (like a pencil) and the top will push back, forcing the stem against that object, and friction will cause the stem to roll along and trace the edge of the object. In this design the stem will trace along the edge of a metal spiral, clinging to it like a magnet- but magnets are NOT involved here. The key to this design is to make the contact point/tip of the top at its own center of mass, then any frictional force in contact with the stem will produce a torque about the contact point at right angle to the direction of friction that creates the stabilizing force (students of physics may recognize application of the right hand rule here). An extreme physics toy! Produced in small quantities 20 years ago, unfortunately hard to find for sale now.

Thermochromic Liquid Crystal Mood Necklace

Similar mood jewelry available here: 
From Etsy: BUY NOW Liquid crystal jewelry

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Thermochromic Liquid Crystal “Mood” Necklace: heat from a hand brings out the temperature dependent color change of the liquid crystal. The molecules of the liquid crystal change orientation and spacing during the phase transition from liquid (warm) to crystal (cool). The molecular configuration shift allows for different diffraction effects producing the color shift. 

Thermochromic Chiral Liquid Crystals

Available here: 
Liquid crystal sheets, thermochromic fun!: 
From Educational Innovations: BUY NOW liquid crystal thermometer sheet 

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Thermochromic Chiral Liquid Crystals: the thin layer changes color as the molecules of the liquid crystal change orientation and spacing during the phase transition from liquid (warm) to crystal (cool). 


Perspective Anamorphosis

Get the Mind Games kit with 15+ amazing items including a balance bird and a rattleback! 
From Quirkology: BUY NOW Mind Games Set 
Also available here: 
From Amazon: BUY NOW Mind Games Set 
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Perspective Anamorphosis: oblique graphical projection creates a wonderful 3D illusion, implemented here with color printing and cutout card-stock. This illusion is part of the Mind Games set of illusions, physics toys, and psychological toys. Special thanks to Prof. Richard Wiseman, creator of Quirkology, for sending me this set! 

Iron Filings in Silicone Oil Suspension

Available from these fine sources: 

From Amazon: BUY NOW Magnetic Field Viewer Set (get the demo set)

Similar device here:
From Educational Innovations: BUY NOW Magnetic Field Viewer with Magnet 

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Iron Filings in Silicone Oil Suspension ( Iron filing field detector ): visualizing the invisible- the magnetic field lines around a horseshoe magnet. In the presence of a magnetic field, ferromagnetic materials (such as iron) temporarily become magnets. Here the iron filings become dipole magnets and link up and align like tiny compass needles to follow and reveal the magnetic field lines associated with the permanent magnet underneath. Viscous silicone oil temporarily keeps the iron particles suspended yet allows for rotation and repositioning under the influence of the magnetic field.

 


Aqua Drop Puzzle

Three models/colors to choose from: 
From Amazon: BUY NOW Aqua Drop Puzzles 

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Aqua Drop Puzzle: a superhydrophobic coating allows this dexterity puzzle to use a drop of water as the "pinball". The white surface is a silica nano-coating that makes water roll off- a condition sometimes referred to as the Lotus effect because leaves of the Lotus plant have this property. 

Chaotic Fidget

This is the exact one used in the video- works well! 
From Amazon: BUY NOW Double Pendulum Chaotic Fidget 

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Chaotic Fidget: a double pendulum spinner- chaos in the palm of your hand! This miniature double pendulum is made from stainless steel, which provides high mass so one can feel the unbalanced center of gravity shift about, and bearings in the joints allow for smooth and sustained motion. Slow motion reveals the intricacies of the chaotic motion, characterized by extreme sensitivity to initial starting conditions, tiny differences in how the system is released leads to dramatically different outcomes each time. 

Top Secret

This physics toy top is available here: 

From Amazon: BUY NOW Mystery Spinning Top

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The amazing green magnetic viewing film is also available: 
From Educational Innovations: BUY NOW Magnetic Field Viewing Film 

Here is the 1974 patent showing the very simple circuit of this device. The spinning dipole (the top itself) induces a current in one of the coils, and this current is fed to the base of the transistor turning the electromagnet on when the top is near. 
 

"Top Secret": this top will stay spinning for more than a week- because it is actually a motor! The top is a dipole magnet (as revealed by Magneview film) and the base has an electromagnet that gives the dipole a push when the top comes near the center. An ingeniously simple circuit consisting of only a battery, a coil, and a transistor, is activated when the spinning magnet nears the coil turning on the electromagnet to give a boost to the spin of the magnetic top.


Weighted Rattleback:

This beautiful weighted version is available from this shop in Germany: 
From experimentis-shop.de: BUY NOW Weighted Rattleback 

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See other rattleback designs in my collection here (and some links to the physics!) 

Weighted Rattleback: prefers to spin counter clockwise. If spun clockwise, a complicated combination of friction, precession, and instability induced vibrations transforms the rotational energy into into rattling (energy of oscillations) and then into rotational energy in the opposite direction! For this rattleback design the wood bottom is symmetrical, and the preferred direction behavior is related to the asymmetric placement of weights near the ends which are slightly rotated off of the line of symmetry. 

Acrylic Rattleback

These acrylic versions work great and are inexpensive: 
From Educational Innovations: BUY NOW Rattlebacks 
From Amazon: BUY NOW Rattlebacks 

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Acrylic Rattleback: a favorite from my collection- prefers to spin counter clockwise. If spun clockwise, a complicated combination of friction, precession, and instability induced vibrations transforms the rotational energy into into rattling (energy of oscillations) and then into rotational energy in the opposite direction! This behavior is related to the asymmetric shape of the bottom of this kind of rattleback, it's somewhat propeller shaped with an "S" curve along the bottom ridge


Diamagnetic Trap Sculpture

This particular sculpture is no longer available, however, Educational Innovations has this nice and affordable starter kit: 
From Educational Innovations: BUY NOW Diamagnetic Levitation Kit 

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Diamagnetic Trap Sculpture: a thin disk of pyrolytic graphite hovers and spins in stable equilibrium over a bullseye configuration of magnetic poles. Diamagnetic substances become temporary magnets while immersed in an external magnetic field, and the created diamagnetic field always opposes the external field (in contrast to ferromagnetic substances like iron which attract). Graphite of this type is one of the strongest diamagnets known, and will levitate over a powerful array of neodymium magnets. ✨With sincere appreciation to Tim Rowett for this kind gift. 

Bubble Trouble Puzzle

This hard to find puzzle is sometimes found here: 
From magicorum.com: Bubble Puzzle

See more physics puzzles: featured physics puzzles

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Bubble Trouble Puzzle: physics brain teaser- the trick here is to move all air bubbles to the center bulb. As with all puzzles featured here on @physicsfun, the solution relies on some fun basic physics principles- can you figure out which ones? Swipe to reveal solution.


The Planets of Our Solar System to Scale

Made by Jay Fisher- Buy the Solar System! 
From Shapeways: BUY NOW Scale Model Solar System 

See also: this 2D scale model of our Solar System

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The Planets of Our Solar System to Scale: 3D printed accurate scale model of 8 planets and Earth’s moon. Wonderful detail allowed by the 3D printing process reproduces the belting on the gas giants. In this model: Earth (diameter = 0.80 cm) and Jupiter (diameter = 9.0 cm)- swipe to see a comparison of the Earth to the Great Red Spot on Jupiter (a hurricane type storm in the Jovian clouds that is more than 500 years old). The ring system of Saturn is color printed on transparency film- swipe twice and note that the inner ring edge to the outermost ring measures 73000 kilometers and could fit almost 7 Earths side by side. The rings around the actual planet are very thin, about 1 kilometer thick, so the transparency film is 250 times too thick to be to scale, and even just the thin 0.010 mm ink layer on the film is 20 times thicker that the actual rings would be at this scale! Made by artist/maker Jay Fisher using images from NASA. 

Globe of the CMB

Produced by George Ioannidis and The Little Planet Factory: 
From Shapeways: BUY NOW Cosmic Microwave Background Globe 

Note: this site contains affiliate links for which I may be compensated

The Cosmic Microwave Background radiation on Wikipedia. 

Globe of the CMB: measuring 7cm in diameter this 3D printed globe shows the temperature map of the entire sky in the microwave frequency range- and shows the Cosmic Microwave Background radiation, the light of the photons left over from the Big Bang. If your eyes could see microwaves this is a map of what the sky would look like- hot and cold patches -a few parts per million difference between red (hot) and blue (cold). This mapped globe depicts the actual data from the orbiting Wilkinson Microwave Anisotropy Probe (WMAP) research team. These tiny temperature fluctuations from 13.7 billion years ago are directly related to the current large scale structure of our universe.

Reaction Rocket

The essence of a great physics toy: simple inexpensive design showing complex physics 
From Educational Innovations: BUY NOW Reaction Rocket 

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Reaction Rocket: projectile launch via momentum transfer in slow motion. The superball/straw base bounces off the table top and then immediately collides with the bottom of the rocket sending it off with a velocity slightly less than 3 times the velocity of the rising ball (true if the ball is more than three times the mass of the rocket). Newton's third law in action! Note that the rocket rises much higher than the drop height (up to 9 times higher).