All physicsfun toys

Puzzle in a Puzzle: Extra Square

Get this and other amazing math puzzles here:

From Etsy: BUY NOW: Extra Square Puzzle

See also: Matsuyama's Paradox

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Puzzle in a Puzzle: 12 pieces fill both large square areas- but the bottom has 5 tiny squares in its center compared to 4 in the top. All 9 tiny squares are identical in size, and the large square areas are also identical. So where did the extra square go? Some fun math involved in the design of this puzzle, which illustrates how the concept of area can challenge our intuitions. Another precision crafted puzzle by Jeux Efcé game shop. 

 

Four Mirror Kaleidoscope 

Other kaleidoscopes by this artist: Apres la Pluie

High quality kaleidocsopes available here:
From Etsy: BUY NOW: Fine Art Kaleidoscopes

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Four Mirror Kaleidoscope: this addition to my collection is unique and strange for two reasons- instead of the usual hexagon pattern (3 mirrors) we have a square grid layout (4 mirrors), and on the end where the light comes through, an odd hologram of an eye as if the scope is looking back at you! Weird and wonderful from artist Dominic Stora of Après la Pluie gallery.


Heritage Periodic Table

The Collector's Edition Periodic Table with 85 element samples and the exact version in video: 
From Etsy store ProtoshopLLC : BUY NOW Heritage Periodic Table

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Alert: only this brand I know of that is guranteed to have the real elements embedded- beware that many very cheap fakes are being sold under $100 US. 

The Heritage Periodic Table: Collector’s Edition- a comprehensive collection of the chemical elements that can fit in the hand. Embedded in acrylic are actual samples of 85 of the 118 elements- including pure gasses and reactive alkali metals in glass ampules- and represented by 80 high purity samples (including a Gold nugget and liquid Mercury) and 5 compounds. Radium is included in the form of an antique watch hand, and the bead of Mercury rolls back and forth within its glass container. This spectacular table and collection is the creative work of Tim and Cory Marriott of Engineered Labs Protoshop LLC

Moire Array Cards

This vintage set sometimes found on eBay. Here are some similar explorations in book from that come with the transparent grids:

From Amazon: BUY NOW: Optical Designs in Motion, and Magic Moire

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Moiré Array Cards: four cards from a 1986 vintage set of paper and acetate prints from TedCo Inc educational supplies. Radial lines exhibit constructive and deconstructive interference patterns that move rapidly from slight motion of the cards relative to each other.