DIY

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

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!

Magnetic Suspsension Sculpture

This DIY magneits sculpture can be assemebled with these parts.  Bring a magnet into a craft shop to find some necklace chain that is non-magnetic. 

From Amazon/eBay: BUY NOW: Quilting HoopNeodyumium Sphere Magnets

Magnetic Suspension Sculpture: two neodymium magnets on chains suspended by their mutual magnetic attraction in this prototype kinetic sculpture. These powerful magnets hold the chains taut with about a 2cm gap. Made from a quilting hoop where the magnets connect under their own force to steel nails soldered on to non-magnetic chain.

Frabjous Geometric Sculpture Puzzle

Get one here- five colors to choose from:

From MoMath: BUY NOW: Frabjous Sculpture Puzzle

Frabjous Geometric Sculpture Puzzle: 30 identical laser cut acrylic pieces interlock into 12 interconnected five point stars (each with a spiral vortex center) in this puzzle based of the Frabjous sculpture by artist and professor of mathematics George Hart (Prof. Hart is now on Instagram, follow him at @george.hart.sculptor to see more of his amazing work.) Note that if one connects the tips of the stars one gets the outline of a dodecahedron, with its 30 edges and 12 sides, and if one considers the face planes of the linked pentagrams the underlying shape is a polyhedron called the “great rhombic triacontahedron”. A year or so ago I got to visit the National Museum of Mathematics in NYC where I bought this puzzle in the @momath1 museum shop. This puzzle was great fun to assemble- buy one to support this inspirational museum, and make a great sculpture for your bookshelf! 


Cartesian Diver

Glass divers available here: 
From Amazon: BUY NOW Glass Divers or this complete set Cartesian Diver Kit

Inexpensive and fun diver kits to make in a bottle available here: 
From Educational Innovations: BUY NOW Cartesian Diver Kits 
 

Cartesian Divers: increasing pressure on the water compresses the air bubbles in the small glass vials filling them further with water making them sink. Pascal's principle states that any change in pressure on an enclosed fluid (such as pushing on the rubber cover) is transmitted evenly to every part of the fluid- the physics of hydraulic brakes! Named after the physicist and philosopher Rene Descartes.

Salt Fractionation

All the ingredients are available from your local market/drugstore. The trick is to find a dye that works for acetone, but will not color water- believe it on not blue glitter will color the acetone nicely and not change the salt water. Follow this link for details: 
ChemEd X: Blog of Prof. Tom Kuntzleman 

Of course Amazon has what you will need:

From Amazon: BUY NOW 
acetoneblue glitterfood coloring, cool bottle 

Salt Fractionation: two liquids that won’t stay mixed! Acetone (dyed blue) floats on top of the higher density salt water (dyed orange). Acetone usually dissolves in water through hydrogen bonding interactions, but solubility can be altered. In a process called “salting out” a sufficient amount of salt is dissolved such that the water molecules, which are much more attracted to the resulting Na+ and Cl- ions (through ion-dipole bonds), will then ignore the weaker acetone hydrogen bonds. This results in the spontaneous separation (shown here in real time) of the liquids no matter how well shaken up. 

Ferromagnetic Interaction

Here is the NdFeB neodymium magnet used in this video:

From Amazon: BUY NOW: Neodymium Disk Magnet

Please use cuation when handeling strong magnets like this one. Small nails, paperclips, staples and other houlshold object made with iron will interact interestingly with the magnetic feild. 

Ferromagnetic Interaction: iron rich nails temporarily become dipole magnets in the presence of an intense magnetic field from a large neodymium super magnet. Here the neodymium disk magnet is set with its north pole pointing up, so the point of each nail becomes a south pole (repelling each other) and the head of each a north pole. Imbued with these temporary induced fields, the nails will try to align themselves with the neodymium dipole’s field like compass needles, and the nails will interact with each other in interesting ways.


Gravity Defying Nail and Magnet

Neodymium magnets will produce the largest gap when suspending a nail.
Please use exterme caution when handling these magnets. 

From Amazon: BUY NOW: Neodymium Super Magnet

Magnetic Defiance of Gravity: a nail suspended between a chain and a powerful neodymium magnet. Ferromagnetic attraction over a distance of many millimeters, and a reminder of the presence of the typically invisible electromagnetic forces all around us. Make your own with a paperclip, string, and a refrigerator magnet- or get a neodymium magnet and see how massive an object you can suspend in air. 

Light Pipe Sculpture

Get an affordable pre-bent light pipe demo here:
From Amazon: BUY NOW: Light Pipe Demo

Blue laser pointers (445nm) available here:
From eBay: BUY NOW: Blue Laser
but any color laser will work. 

Make your own abstract light pipe sculpture, an inexpesive heat gun is the only needed tool:
Materials from eBay: BUY NOW: Acrylic Rod
Tool from Amazon: BUY NOW: Heat Gun

Light Pipe Sculpture: internal reflection constrains most of the laser light to propagate along the bent acrylic rod- the physics of fiber optics. This abstract sculpture was created by applying a heat gun to a 3/8” diameter acrylic rod. The laser pointer used here is blue at a wavelength of 445nm.

Micro Hoverboard

If you want to make one of these you will need: 
1) some pyrolytic graphite (which can easily be sliced and carved): 
From eBay: BUY NOW Pyrolytic Graphite 
2) some neodymium magnets: the racetrack magnets are a bit pricey though! 
From eBay: BUY NOW Diamagnetic Levitation Kit
3) shrink and print this image on medium weight paper, 
and 4) cut and assemble! 

Micro-Hoverboard: diamagnetic levitation technology- although Marty McFly would have to be three inches tall to ride this hoverboard. Made from printed paper and pyrolytic graphite with concentric circular neodymium magnet array. The magnetic rings alternate between north and south magnetic poles in just the right way to trap this special type of graphite. Pyrolytic graphite has strong diamagnetic properties such that it develops an opposite (but weak)magnetic field when in the presence of a magnetic field from another source. Swipe to see the graphite pieces levitating individually.


Gauss Gun

Similar device available here: 
From Amazon: BUY NOW: Gauss Gun

Easy to make with these magnets:
From eBay: BUY NOW Magnets for Magnetic Cannon DIY and  Steel balls for Magnetic Cannon DIY

Gauss Gun: acceleration of steel balls through magnetic potential energy and cascading collisions. Four neodymium magnets provide the potential energy that is converted into significant kinetic energy of the end steel ball. The initial configuration has two steel balls on one side of each magnet- an incoming ball on the opposite side accelerates and impacts each magnet in turn sending each loosely connected second ball off with greater speed. 

Centripetal Kinetic Toy

This "iBall" desk toy is no longer in producltion. Howerver, a similar version of this toy can be made from these components:

From Amazon: BUY NOW: two piece acrylic shell

From Amazon: BUY NOW: 1/4 inch ball bearings

Centripetal Kinetic Toy: seven rolling steel balls hug to the inside of the acrylic sphere given sufficient velocity. Here the balls are launched such that their orbits are in the same plane, and due to their angular momentum (and a torque due to gravity) the plane of rotation precesses like the axis of a spinning top until friction slows them down. This toy was made in 2007 (sadly no longer in production) and marketed under the name "iBall". 

Disappearing Spoon

Gallimum metal and a silicone mold to produce the spoon- available here:

From Amazon: BUY NOW: Gallium Mold Spoon Kit 

Disappearing Spoon: the metal gallium has a melting point of 30°C (86°F) and will melt quickly when exposed to tea temperature hot water- or melt in one’s hand if handled too long. This spoon was made with a silicone mold (swipe to see process), and feels and sounds just like a regular spoon, except solid gallium is brittle and the spoon can shatter like glass if dropped. An amazing parlor trick as well as a classic and historical class demonstration.


Diamagnetic Racetrack

Simiar diamagnetic levitation kits are available here: 
From eBay: BUY NOW Diamagnetic Levitation Kit

Diamagnetic Racetrack: thin pyrolytic graphite sheets levitate above powerful magnets. A set of five concentric neodymium magnets, alternating N-S-N-S-N comprise the racetrack and form the trapping field. Diamagnetic substances develop temporary repulsive magnetic fields only when they are in the presence of a magnetic field from some other source. Graphite of this sort is the most diamagnetic substance known.

Magnetic Influence on Aluminum

For this demonstration stronger magnets work best:
From Amazon: BUY NOW: Neodymium Magnets

Here is a good small turntable with bearings: 
From Amazon: BUY NOW: Spinning Base

Magnetic Influence on Aluminum: physics puzzler- spin a magnet under a beer can suspended by a thread, and the can will turn. Why? Aluminum is not ferromagnetic, and as shown, magnets are not attracted to the can.  So how does a spinning magnet influence the can to spin? 

 

 

 

Answer: the can spins due to eddy currents induced in the conducting aluminum due to the moving magnetic fields underneath. The eddy currents make the can into a temporary electromagnet that then interacts with the magnets below according to the famous law by Lenz.

Unmixing Density Column

The bottle used here is from Voss Water: a nice cylinder and the labels come off easily. Amazon has the ingedients:

From Amazon: BUY NOW 
acetoneblue glitterfood coloring, Voss Water

The density column I made for this video is based on blend of two ideas: this "science snack" from the exploratorium: Klutz-Proof Density Column and this ChemED X post: Blog of Prof. Tom Kuntzleman  

See my Salt Fractionation post for details. 

Unmixing Density Column: three liquids that won’t stay mixed! Acetone (dyed blue) floats on top of the higher density vegetable oil, which in turn floats atop salt water (dyed orange) which is more dense than oil. Acetone usually dissolves in water through hydrogen bonding interactions, but solubility can be altered. In a process called “salting out” a sufficient amount of salt is dissolved such that the water molecules, which are much more attracted to the resulting Na+ and Cl- ions (through ion-dipole bonds), will then ignore the weaker acetone hydrogen bonds. This results in the spontaneous separation of these three liquids no matter how well shaken up. 


In Defiance of Gravity

Neodymium magnets will produce the largest gap when suspending a nail or other iron rich objects.
Please use exterme caution when handling these magnets. 

From Amazon: BUY NOW: Neodymium Super Magnet

In Defiance of Gravity: a 3 oz plumb bob in suspension between a chain and a powerful neodymium magnet. Ferromagnetic attraction over a distance of many millimeters, and a reminder of the presence of the typically invisible electromagnetic forces all around us. Sculpture: oak, stainless steel chain and hardware, neodymium super magnet, standard plumb bob tool. Iron filings in oil align and chain together to reveal the magnetic field lines of the equilibrium configuration.

Electric Motor/Generator

Amazingly this motor is available for less than $10 US. 

From Amazon: BUY NOW: Brushless Motor/Generator with LED

Electric Motor/Generator: this inexpensive and common motor can also serve as a generator of AC electricity- here lightning an LED when the shaft of the rotor is spun by hand. Most electrical energy we use today is produced by moving a magnet near a coil of wire (known as Faraday’s law of induction) to produce an electric current. Removing the permanent magnet casing reveals this design to use 9 separate copper windings. I made a transparent second rotor with six neodymium magnets- and when these magnets are made to move near the windings the LED again lights with the flow of current. Swipe to see the beautiful magnetic field pattern of the rotor design using magneview film.

Bismuth Diamagnetic Levitation

Get these 99.9% pure element Bi 83 cubes here:
From Luciteria: BUY NOW: Bismuth Element Cube

Many combinations of strong neodymium magnets will work, here are the versions I used:
From Amazon: BUY NOW: Cylindrical Neodymium Magnet
From eBay: BUY NOW: Tiny Neodymium Cube Magnets

See my video of other pure element cubes by Luciteria Science

Bismuth Diamagnetic Levitation: Element 83 (bismuth) is the most diamagnetic of the elements*. Here a small neodymium magnet is made to float between two 99% pure bismuth 10mm cubes which are held in precise configuration by friction with the parallel walls of the acrylic assembly I made. Diamagnetic substances only have magnetic fields of their own when placed in an external magnetic field from another source- here the tiny cube magnet supplies the field. Diamagnetic fields are pretty weak though so a powerful cylindrical neodymium magnet sits above the cubes and is adjusted to help lift the tiny cube magnet against gravity. *except for a special form of carbon known as pyrolytic graphite.