All physicsfun toys

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. 

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. 

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 ?


Thermochromic Eclipse Postage Stamps

Available from the US Post Office and here: 
From Amazon: BUY NOW Thermochromic Eclipse Stamps 

Thermochromic Eclipse Postage Stamps: In commemoration of the total solar eclipse next Monday the US Post Office has released their first ever stamp featuring thermocromic ink. Thermotropic liquid crystals go from opaque to transparent during a phase change from a crystal to liquid state. Here the warmth of the hand reveals the face of the moon in front of the solar corona. The first physics toy stamp! 

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


Thermochromic Liquid Crystal Mood Necklace

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

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. 

The PiTOP

Well engineered brass spinning toys by SiriusEnigmas

From Etsy: BUY NOW: The PiTOP

The PiTOP: this beautiful brass cylinder has a radius of 1 inch, a height of 1/π inches, and displays the first 109 digits of π on its face. Spin this disk (best with sound on) and it will demonstrate some very interesting physics involving energy transfer and conservation of angular momentum. The edges of the cylinder are rounded and engineered to exhibit an optimum motion of a “spolling” coin, a motion that combines spinning and rolling (closeup shown in 240fps). As the disk’s angle of inclination decreases the speed of the rolling increases dramatically until the contact point with the mirror is moving in excess of 200mph. From the mind of physicist Ken Brecher, inventor of the PhiTOP. Note also that with the specified height, that the volume of this cylinder is exactly 1 cubic inch! 

Maxwell's Dynamical Top: Historical Replica

Get this accurate and beautiful 1/2 scale replica here:

From Machined Marvels: BUY NOW: Maxwell's Dynamical Top

Maxwell’s Dynamical Top: one of my favorite demonstrations of the strange properties of rotating bodies- shown here with a 1/2 scale but exacting replica of the famous “Dynamical Top” created and demonstrated by the great physicist James Clerk Maxwell in 1857. When this brass bell shaped top is spinning an interesting stability can occur- push on the pointed stem 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. Note- 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 a right angle to the direction of friction that creates the stabilizing force (students of physics may recognize application of the right hand rule here). This beautiful historical replica is now available from machinist and creator Jim Peever @machinedmarvels- and as far as I know the only other replicas of this device where made in the 1880’s!


Dancing Ferrofluid Device

Available here:

From Amazon: BUY NOW: Venom Sound Dancing Ferrofluid Display

Dancing Ferrofluid: a black 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. Featuring “12 String Thing”, composed and performed by my good friend T.D.Clark @tdclark67 

Zigzaging Balance Wine Rack

The 3D print file for this amazing device is available here:
From Thingverse: Balance Wine Rack by Kenneth79

Similar balance wine racks available here:
From Etsy: BUY NOW: Balance Wine Rack

Zigzagging Balance Wine Rack: a carefully engineered 3D print version of this famous demonstration- the center of mass of the rack/wine bottle system is directly over the base providing unstable equilibrium for this balancing act. A 3D print design by Kenneth Hansen which looks metallic and fantastic in shiny PLA. Suspended here is Educated Guess by Roots Run Deep, an excellent cabernet sauvignon from the North Coast.


Lenticular Lithograph

Kinetic lenticular lithographs from Jeff Johnson available here:

From eBay: BUY NOW: Lenticular Lithographic Art

Lenticular Lithograph: amazing art from the 1990s by Jeff Johnson that uses an array of thin acrylic cylinders to produce this three image crossfade effect. As the viewer moves from one vantage point to another the geometric image morphs from among three designs. I obtained this artwork slightly damaged- it was missing some of the cylindrical lenses- but I was able to purchase the right size acrylic rod to make the needed repairs (swipe for details and added insight to how this lenticular effect is achieved).