Recent Posts

Lenticular Invisibility Sheet

This item came to me in my Curiosity Box subsciption:
Get (or give!) a Curiosity Box subscription here: JOIN NOW: The Curiosity Box

Inexpesive "lenses" showing this effect available here: 
From Amazon: BUY NOW: Lubor's Lens

Giant versions availabe here:
From Etsy: BUY NOW: Invisibility Lens

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Lenticular Invisibility: this thin acrylic sheet is comprised of tiny cylindrical lenses which can allow images to be out of focus along one dimension which blurs thin images and hides them. This 70 lens per inch sheet is part of a lenticular optics kit that came as part of my Curiosity Box subscription- amazing and fun!

Rhythmic Ferrofluid

Get this affordable ferrofluid device here:

From Etsy: BUY NOW: Iridescent Ferrofluid (select option "rhythm machine")

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

Rhythmic Ferrofluid: an iridescent magnetic fluid interacts with a variable strength electromagnet (like those found in speakers). A circuit supplies power to the electromagnet in proportion to the sound waves picked up by a microphone, the changing magnetic field- combined with the liquid surface tension of the colloidal ferromagnetic liquid- produces the captivating motion that keeps time with any music played. 

Wringing Guage Blocks

Guage block sets can be a bit pricy, but some fairly inexpensive pieces and small sets can be found for demonstrations and such:

From Amazon: BUY NOW: Gauge Blocks

Wikipedia has a nice description of Gauge Blocks and the Phenomenon of Wringing

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Wringing Gauge Blocks: two blocks of metal (not magnets!) will stick together by a process called wringing if their surfaces are flat to high precision- such as these gauge blocks found in most machine shops. Here two blocks are forced apart with a snap, and then wrung back together with the characteristic sliding motion technique. Gauge blocks are flat to less that one millionth of a meter and are used by machinists for precision length measurements and calibration. The science of the wring force remains somewhat a mystery and no one has yet found a fully excepted physics description- but we do know that blocks will wring in a vacuum and that the force can be up to 30 times that of weight of the blocks. Fun physics from the shop!

Anamorphic Locomotion Cup & Saucer II

Animated bird set available here:
From Amazon: BUY NOW: Luycho Locomotion Cup & Saucer 

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

Locomotion Anamorphic Cup & Saucer: Another expertly crafted product from @luycho using an amazing combination of barrier grid animation and anamorphic projection rendered on elegant porcelain. The warped image on the saucer is reconstructed by reflection off the surface of the cup, however the gold mirroring is comprised of parallel lines that only reflect part of the image pattern. Turing the cup (or the saucer and cup together) reveals a flying bird! 

Matsuyama's Paradox

Get this and other amazing math puzzles here:

From Etsy: BUY NOW: Missing Square Puzzle

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

Matsuyama’s Paradox: dissect a large square in to four equal quadrilaterals, rotate and reassemble- to find a small square is missing! Where did the additional area come from? Fun math involved in the design of this puzzle, which illustrates how the concept of area can often challenge our intuitions. Swipe to compare the two assemblies. A precision crafted puzzle by Jeux Efcé game shop. Wikipedia has good details: Missing square puzzle

Impossible Bottle with Arrow

Get an impossibe object from this artist here:

From Etsy: BUY NOW: Impossible Bottles and Objects

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

Impossible Bottle with Arrow Sculpture Puzzle: a new seemingly impossible object in my collection- Created with clever engineering, this “impossible” syrup bottle contains a wooden arrow that should not fit through its neck. The wood of the arrow is notably one uncut piece, and yet a metal washer is also somehow trapped on the shaft of the arrow. The puzzle aspect is to consider how the bottle was produced (I personally have some theories- but I do not know the secrets of this artist). I can tell you with high certainty that the bottle was never cut or altered in anyway, and it was not somehow formed around the objects. This bottle by Brad Byers is an expertly crated example of the impossible object genre.

Hero's Engine

This live steam engine is available here:

From EngineDIY: BUY NOW: Hero's Engine

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Hero’s Engine: the very first steam engine ever devised, the Aeolipile is a radial steam jet reaction turbine, an a invention attributed to Hero of Alexandria in the year 1 AD. Water within the spherical container is heated to produce steam which exits through nozzles directed at right angles to the radial direction, and by Newton’s third law these jets produce a torque about the rotation axis. There is no historical record of this engine being put to practical use in ancient times- except perhaps as the world’s first physics toy!

Candle Powered Lava Lamp

This model available here:

BUY NOW: Candle Powered Lava Lamp

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

Candle Powered Lava Lamp: a tea-light candle provides the illumination and the heat source in this newest incarnation of the famous lamp. The base and cap are glazed ceramic and it takes about one hour for the fluid motion to begin. The Lava Lamp is a kinetic art form with an amazing amount of physics on display: convective heat flow, Archimedes principle, surface tension (note how the smaller blobs form into spheres), and immiscible liquids to name just some of the science behind this famous device. Manufactured by Mathmos and invented in 1963 by Edward Walker of Dorset, England. 

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 Amazon: 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!

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

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. 

Octogon Infinity Lamp

From EP Designlab: BUY NOW: Octogon Infinity Lamp
Special discount for @physicsfun followers on all EP Lights products
use coupon code: PHYFUN (10% off) 

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Octagon Infinity Lamp: parallel partially mirrored panes with multi colored LEDs create the illusion of depth through the physics of reflection and refraction. This design incorporates selectable programmed color shift patterns that add a dynamic motion component to the classic infinity mirror concept. 

Happy Meal Physics Toy: Tippe-Tops

These vintage toys often available here:
From eBay: Search Now: McDonald's Flipover top

Get a nice tippe-top from this fine source: 
From Etsy: BUY NOW Flip Over Tops

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Happy Meal Physics Toy: back in the 1980s McDonald’s included Ronald and Grimace tippe-tops (the classic flip-over physics toy), with even more physics fun from a magnifying lens formed in the clear plastic that distorts and enlarges the images of these famous promotional characters. These tops work great! Tippe-tops demonstrate complex physics: friction with the surface provides a torque that acts on the existing angular momentum of the top to flip it over. The top will stay flipped until the spin rate slows down enough to where its center of mass pulls it back to the resting position.

Gravity Drop Challenge

Get this well made demonstration here:

From Etsy: BUY NOW: Gravity Path Demo Puzzle

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Gravity Drop Challenge: starting at the same height, and ending at a same lower height, which path will take the shortest amount of time? The straight line (red marble) or the wavy longer path (blue marble)? The weird thing is that both marbles will have identical speeds at the finish line- yet one gets there quicker. The physics problem of finding the curve of fastest descent is called the brachistochrone problem- from the Greek words brakhistos ‘shortest’ and khronos ‘time’- and it is not a straight line. The fastest curve turns out to be the cycloid- a topic for a future post.

Projection Kaleidoscope 

Get this fun DIY kit here:

From eBay: BUY NOW: Projector Kaleidoscope Kit

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Projector Kaleidoscope: mirrors, symmetry, and the physics of optics are all explored through the assembly of this unique projector kaleidoscope project. Invented by the famous Scottish physicist Sir David Brewster (1781-1868), the kaleidoscope is one of the most popular physics toys ever sold.

The Swinging Sticks

Available in desk top (small) or origial (large) versions:

From Amazon: BUY NOW  Swinging Sticks Kinetic Sculptures

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The Swinging Sticks: a driven coupled chaotic physical pendulum as kinetic art where the placement of the rods' axes of rotation are engineered to exhibit the widest range of interesting motion. Four AA batteries and a simple electromagnetic kicker circuit in the base gives a tiny push to a magnet in the end of the large rod, keeping the system in motion for over a year! Perhaps one of the most famous physics toys out there as it was featured in the movie Iron Man II (sitting on the desk of Pepper Potts).

Buxstix: Revolving Tensegrity Sculpture

Get this well made and unique device here:

From Etsy: BUY NOW: Buxstix Tensegrity

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

Revolving Tensegrity Sculpture: three stainless steel struts are held in stable equilibrium by elastic tension in this elegant desk toy by architect and inventor Stephen Lawrence. Entitled “Buxstix”, this manipulable fidget includes an acrylic base and three glow in the dark beads that slide in curious motion. Another fun take on the tensegrity concept, invented by Kenneth Snelson and made famous by the architect Buckminster Fuller in 1949. 


Vertical Mendocino Motor

Get this device for a great price here:

From EngineDIY: BUY NOW: Vertical Mendocino Motor

From engineDIY: BUY NOW Horizontal Levitating Motor (on all models here-remove brown protective film to reveal clear acrylic on rotor)

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Mendocino Motor:  each face of a solar cell is connected to a coil of copper wire across from the opposing solar cell. When the rotor is lit from one side the lit solar cell provides electric current to the coil in the opposite position which becomes a temporary electromagnet that pushes against the permanent magnets in the base propelling the rotor to rotate. As the rotor turns, the coil that moves into the position near the magnet is likewise energized by the solar cell currently at the top- one can say the light commutates this motor. Magnetic bearings to reduce friction in both models. Invented in the 1960s by Daryl Chapin of Bell Labs and popularized by Larry Springs of Mendocino CA 

Luna Kinetic Illusion Sculptures

The KickStarter page: Luna Kinetic by Mezmoglobe

Similar devices available here:
From Amazon: BUY NOW: Kinetic Illusion

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Luna Kinetic Illusion Sculptures: precision machined and crafted, these kinetic desk toys exhibit a helical motion illusion in which a metal sphere seemingly defies gravity as a coil spins around it. An astonishing design by Kristoph Krisjans and the @mezmoglobe team and made possible by a recently completed Kickstarter campaign- I recently received these two variations.