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Nixie Tube Clock V2

The Nixie Tube Clock in the video is of amazing craftsmanship- real hardwood with brass accents and solid construction. Get one from this excellent shop: 
From Etsy: BUY NOW 
Nixie Tube Clocks 

Nixie Tube Clock V2: long before there were 7 segment LED displays there was the Nixie- cold cathode tubes with a wire mesh and 10 cathodes shaped in the form of numerals 0-9 that illuminate through neon glow discharge. The “Numeric Indicator eXperimental 1” or NIX 1 was introduced in 1955 by Burroughs Corporation and manufactured until the 1990s. This clock uses modern electronics to power Russian versions called the ИH-12A where the numbers are stacked so the front symbols obscure each lighted cathode minimally: from back to front 162750483.

Tiny Leaf Blower Coanda Effect Toy

Get the "World's Smallest Leaf Blower" here:
From Amazon: BUY NOW: Smallest Leaf Blower

An inexpensive supply of styrofoam balls available here:
From Amazon: BUY NOW: Styrofoam Balls Assorted

Tiny Leaf Blower Toy: this little battery operated blower is great for experimenting with the Coandă effect. Here an air stream attaches and wraps around the styrofoam ball trapping it in the center of the stream. As the air changes direction to flow around the ball, momentum is imparted to push the ball against gravity and levitating it in equilibrium. A cylinder constrains the airflow and temporarily changes the dynamics which allows the airstream to push the ball up and out- and if one aims carefully the ball will fall back into the Coandă effect trap. 


Reflection and Refraction of a Cyan Laser Pointer

Get this beautiful new color of laser pointer here: 
From eBay: BUY NOW: 488nm Laser Pointer (Cyan)

Blocks of polished acrylic available here:
From eBay: BUY NOW: clear acrylic block

Reflection and Refraction of a Cyan Laser Pointer: a new affordable wavelength laser pointer that just came on the market- 488nm producing a beautiful hue of blue. The beam is made brightly visible as internal reflection constrains most of the laser light to propagate along the interior of this block of acrylic (similar to the physics of fiber optics).

Thermochromic Safety Sticker

These stickers transition back and forth and can be used on many surfaces. Get some here:

From Etsy: BUY NOW: Thermochromic Saftey Sticker

Thermochromic Safety Sticker: the liquid crystal ester dye in this reusable sticker is calibrated to change color when the surface temperature exceeds 50°C (122°F)- that at which prolonged contact (more than 0.5s) will burn skin. Here the safety sticker is attached to a slab of aluminum and heated with a simple candle- it took about 3.5 minutes for the heat to distribute and bring the aluminum to the threshold temperature. When the surface cools the sticker again appears blank and can transition over and over again

Moiré Kinetic Wheel

Get this device (and other variations) here:

From Amazon: BUY NOW: Moiré Fidget Device

Moiré Kinetic Wheel: sold as a fidget toy this device has two plastic disks and each has a pattern of curved spokes that can rotate independently and produce interesting illusions of motion via moiré interference effects. Explore constructive and deconstructive interference patterns with this minimalist toy.


Poly acrylamide Polymer Vanishing Act

Get some of these grow-spheres here: 
From Educational Innovations: BUY NOW Growing Spheres 

Poly-acrylamide Polymer Vanishing Act: these spheres of hydrophilic polymer have an almost identical index of refraction as that of water- thus when submersed they become invisible. Note the elasticity of these spheres from the way they bounce, while at the same time they refract their surroundings as a spherical lens. The super absorbent spheres start as hard crystals with a radius of 2mm and grow to 11mm when immersed in water. So much physics going on here! 

Pikachu Phonotrope Spinner

Get this fun spinner here:

From Etsy: BUY NOW: Pikachu Animation Spinner

Phonotrope Spinner: When viewed through video from a smartphone an animated Pikachu springs into motion. The laser cut and printed acrylic is specifically designed to interact with the frame rate of the video process, similar to the animation effect of a flip book, but in a repeating cycle. The effect can also be seen without a camera by using a mirror and viewing through the spaces between the cutouts (swipe to see demo which looks much better in person)- using a mirror like this turns the spinner into a phenakistiscope, the 1833 invention that started moving media animation that lead to the development of movies and video. 

Pythagorean Puzzle

Available here: 
From Creative Crafthouse: BUY NOW Pythagorean Puzzle

Pythagorean Puzzle: a proof, in physical form, of one of the most famous equations concerning the sides of any right triangle. The area of a square with side c of the hypotenuse is indeed equal to the sum of the areas of the squares of side a and b. This kit also allows at least two other ways to prove this theorem named after the famous Greek mathematician from 500 BC. One of the most used formulas when calculating vectors in physics classes ?


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.

Stirling Engine

Get this very nice working model engine here, choose a configuration:

From EngineDIY: BUY NOW: Stirling Engine 
From EngineDIY: BUY NOW: Stirling Engine with Generator
From EngineDIY: BUY NOW: Stirling Engine Simple Vehicle  

Stirling Engine: an elegant model of an external combustion heat engine with dual reciprocating pistons which operates by cyclic compression and expansion of air. Heat one cylinder with the cute little alcohol burner and this model gets up to speed quickly. Pyrex glass allows one to view the hot cylinder in operation (shown here in slow motion) and this version of the model includes a small generator to convert some of the mechanical energy into electrical energy which then powers some LED lamps. This design is attributed to Scottish engineer Robert Stirling back in 1816- a working piece of the industrial revolution for your desk top!

 


Horizontal Hand Boiler

This device available here:

From Edicational Innovations: BUY NOW: Horizontal Hand Boiler

Horizontal Hand Boiler: liquid-gas phase transition. The boiling point of dichloromethane is slightly below body temperature and heat from a hand will induce vaporization of the liquid which increases pressure in one bulb pushing the red (dyed) liquid through the glass pipe to the other bulb. The process can repeat by switching the hand to the other side, but as both sides heat up the transfer is less vigorous. An inexpensive toy demonstrating phase changes and other thermodynamic physics. 

Electric Generator Demonstator

Get this demonstation here: 
From EngineDIY: BUY NOW: Electric Generator

I upgraded this version with a larger LED light bulb: 
From Amazon: BUY NOW: 3V LED lightbulbs and E26 Socket

Generator Teaching Demo: The electrical energy that comes to your home is produced by some device somewhere moving a coil of wire next to a magnet to produce an electric current (known as Faraday’s law of induction). This tabletop demonstration uses a crank and belt drive to spin the coil between the north and south poles. The ends of the coil are attached to the two smooth metal pieces on the shaft (the commutator) that makes contact with the output wires and connects to the lightbulb. Maximum current is produced when the axis of the coil is at a right angle to the magnetic field- so the current comes in a series of pulses and the bulb flashes on and off. Physics of energy transfer: mechanical kinetic energy→ electrical energy→ light energy. 


Wireframe Ambiguous Cube

Get the files (or order one printed) here:
From MakeAnything's MyMiniFactory: BUY NOW: Illusion Cube 3D Print Files
From Shapeways: BUY NOW: Ambiguous Cube Illusion

See the other illusions my collection: Ambiguous Objects

Wireframe Ambiguous Cube: another innovation of the ambiguous object illusion invented by mathematician Kokichi Sugihara of Meiji University- this time a 3D frame of a cube transforms to a cylinder! A new 3D print design from @make.anything

Mini Acoustic Levitator

Get this inexpensive device here:

From EngineDIY: BUY NOW: Mini Acoustic Levitator

Mini Acoustic Levitator: small pieces of styrofoam become trapped between areas of higher pressure induced by high frequency sound waves. Ultrasonic transducers placed at the top and bottom are basically speakers that emit sound waves at a frequency of 43,000 Hz, which corresponds to a wavelength of 8mm for dry air. If the transducers are positioned just right standing waves are produce with nodes of low pressure at half wavelength intervals- and low mass objects like these foam pellets will be suspended against gravity when placed near one of these nodes. Here we see a stack of three pellets with a spacing of about 4mm which is the expected distribution of the nodes. To place the pellets into the sound stream without disrupting the standing waves this device comes with a small screen with a handle which allows the sound waves to flow through the holes in the mesh and trap piece of foam. Although the device uses sound it appears silent as the frequency used is way above that which humans can hear (20Hz to 20kHz).

 

ZipString String Projector

Get this amazing device here:

From zipstring.com: BUY NOW: ZipString

ZipString: a loop of string projects upward pushed by two motorized wheels in the handheld base- yes, one can push a string! The result is a mix of projectile motion and viscous fluid flow in this piece of manipulable kinetic art. Explore interesting behavior of wave motion and conservation of momentum with different string loop sizes- a green loop of about 1 meter and an orange loop (swipe to view) of approximately 4 meters. An amazing new physics toy on the market complete with rechargeable bar and 3 string loops of different size.