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Popsicle Stick Bomb

Craft sticke work great:

From Amazon: BUY NOW: Stick Bomb Supplies

Amazingly: There is a Wikipedia entry on Stick Bombs and their physics

Popsicle Stick Bomb: a form of simple tensegrity, the elastic potential energy of the bent sticks is dramatically released under application of a slight concussive force such as an impact with a table top- shown in forward and backward slow motion (swipe to see three more explosions). Featured here is one of the simplest constructions with 5 flat sticks woven into a spring-loaded configuration held in place by friction and tension induced by the bending of the wood. A nice demonstration of energy conversion- potential to kinetic.

Switch Pitch Ball

Get one here: 
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Switch Pitch

SWITCH PITCH BALL Spotted with BILL GATES

Switch Pitch Ball: this spherical assembly changes color by turning inside out when tossed into the air. Advertisements for this toy incorrectly claim air drag is involved in the transformation. The ball is made of multiple components hinged together. In launching the ball from the hand an upward acceleration results in a torque that pivots each component around its center of mass, causing the rotation of these components in an organized way leading to the transformation. Imagine tossing a stick straight up. If the stick is perfectly vertical upon launch it will move straight up- but if it is initially slanted at all it will also begin to rotate upon launch. Similar physics underlies the motion of each component of the ball- shown here in 240 fps slow motion. The Switch Pitch is produced by the makers of the Hoberman Sphere.

Spin Bank

Available from these fine sources: 
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Coin Spin Bank 

Spin Bank: a clever spring mechanism launches each coin into rotation along a symmetry axis on to a concave trapping surface. Angular momentum of the spinning quarter keeps it upright even as it bounces upon impact with the platform. Another spin on making saving spare change fun!


Giant Newton's Cradle

Regular sized Newton's cradles availabe here:
From Amazon: BUY NOW: Newton's Cradle

Newton's Cradle: industrial model made with galvanized aircraft cable, aircraft aluminum for the frame, and 1.5 inch one-half pound nickel plated chrome steel spheres. (0.23 kg and 3.8cm in diameter each) The classic demonstration that shows the curious behavior due to conservation of both momentum and kinetic energy. Swipe to see comparison to standard version.

Diffraction Spectrum Candle

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From Amazon: BUY NOW Rainbow Diffraction Candle 

Diffraction Spectrum Candle: a thin plastic diffraction grating surrounds the flame in this rainbow producing design. The rainbow spectrum is produced not by refraction like that of a prism, but instead by diffraction, where light waves deconstructively and constuctively interfere.


The Levimoon

Get a levitating moon globe lamp here! 
FromAmazon: BUY NOW Levitating Moon Globe Lamp

The Levimoon: this detailed moon globe is an adjustable lamp that levitates! Charged through wireless induction via the base, the moon floats above the Earth while illuminated from the inside to reveal the major features of the lunar surface, and will rotate when given a slight push. This kind of levitation uses a control system with an adjustable electromagnet in a feedback loop with Hall effect sensors which allows for fine tuning of the magnetic field to exactly balance the pull of gravity. 

Well Balanced Cabernet

Similar wine racks available here: 
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Balance Wine Rack 

Well Balanced Cabernet: a carefully engineered acrylic 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. Suspended here is Hypothesis by Roots Run Deep, an excellent Napa cabernet sauvignon. 

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Acrylic Rattleback

These acrylic versions work great and are inexpensive: 

From Amazon: BUY NOW: Rattlebacks 

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

TrueBalance

From Amazon: BUY NOW TrueBalance Coordination Puzzle 

TrueBalance: coordination challenge puzzle- get the six disks, connected by bearing swivels, into a vertical stack by only tilting the handle. Harder than it looks to get each disk’s center of mass above the one below at the same time into the unstable equilibrium final state. The swivels constrain the system, limiting the degrees of freedom, and allowing strange and interesting motion. Kinetic art as a toy! 

Coin Escape Puzzle

Available here: 
From eBay: BUY NOW: Coin Escape Puzzle 

Another puzzles 
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BUY NOW: Puzzles

Coin Escape Puzzle: physics brain teaser- remove the coin without breaking the container or using any tools other than your hands. Of course you spin it to get the quarter out- but exactly how? The solution to this puzzle (like others featured here) relies on some fun basic physics of spinning things. Answer below and swipe to reveal solution. 


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The Lollipopter

Four styles to choose from: 
From Amazon: BUY NOW: Lollipopter Kinetic Art 

The Lollipopter (The Helicone): one of my favorite interactive kinetic sculpture designs. With a bit of practice one can master the transformation in both directions: A snap of the wrist imparts angular momentum to the "petals" which then rotate until an internal mechanism stops their motion with predetermined spacing- a helix transforms to an abstract pine cone. A second snap of the wrist in the opposite direction returns the helix. A creation by artist John Edmark. 


Spinning Liquid Paperweight

Many versions available here 
From Amazon: BUY NOW Liquid Wave Paperweight Toy 

Spinning Liquid Paperweight: two immiscible liquids (three if you count the air bubble) are sorted under gravity by density with the densest on the bottom and the lightest on top. If the container is rotated the boundary between the layers forms a parabola due to the added influence of centripetal acceleration. As seen here in 240 fps slow motion, symmetric waves travel and reflect along the curved surface for the first few rotations until damped out via viscosity and friction. The plastic fish have a density between that of the two liquids so they stay at the boundary layer. 

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.