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Astrojax
Astrojax, invented in 1986 by Larry Shaw, is a toy consisting of three balls on a string. In the original version of the toy, one ball is fixed at each end of the string, and the center ball is free to slide along the string between the two end balls. Inside each ball is a metal weight. The metal weight lowers the moment of inertia of the center ball so it can rotate rapidly in response to torques applied by the string. This prevents the string from snagging or tangling around the center ball. Roughly, Astrojax play is a cross between juggling, yo-yo, and lasso. A wide variety of tricks and maneuvers can be performed with it. The basic orbits are vertical orbits, horizontal orbits and a figure-eight (butterfly) pattern. History Astrojax has been used to teach physics at the grade school, high school, and college levels, NASA has taken Astrojax into outer space as part of its Toys in Space education program, and Astrojax has even been the subject of research on nonlinear dy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Links
An internal link is a type of hyperlink on a web page to another page or resource, such as an image or document, on the same website or domain. It is the opposite of an external link, a link that directs a user to content that is outside its domain. Hyperlinks are considered either "external" or "internal" depending on their target or destination. Generally, a link to a page outside the same domain or website is considered external, whereas one that points at another section of the same web page or to another page of the same website or domain is considered internal. Both internal and external links allow users of the website to navigate to another web page or resource. These definitions become clouded, however, when the same organization operates multiple domains functioning as a single web experience, e.g. when a secure commerce website is used for purchasing things displayed on a non-secure website. In these cases, links that are "external" by the above definition can conce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaskan Yo-yo
An Eskimo yo-yo or Alaska yo-yo (; ) is a traditional two-balled skill toy played and performed by the Eskimo-speaking Alaska Natives, such as Inupiat, Siberian Yupik, and Yup'ik. It resembles fur-covered bolas and yo-yo. It is regarded as one of the most simple, yet most complex, cultural artifacts/toys in the world.Kiana, Chris (2004/2016). ''Original 100 Alaska Eskimo Yo-Yo Stratagems: Instructional Book''. Publication Consultants. ASIN: B007SNYM38. /. andKeynote Speaker: Christopher (Chris) J. Kiana, M.B.A., MA-RD, Ph.D., candidate, ''WCSpeakers.com'' (accessed: December 01 2016). The Eskimo yo-yo involves simultaneously swinging two sealskin balls suspended on caribou sinew strings in opposite directions with one hand. It is popular with Alaskans and tourists alike.Klistoff, Alysa J. (2007), Weapon, Toy, or Art? The Eskimo yo-yo as a commodified Arctic bola and marker of cultural Identity'. University of Alaska Fairbanks. . This traditional toy is two unequal lengths of twi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helix
A helix (; ) is a shape like a cylindrical coil spring or the thread of a machine screw. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word ''helix'' comes from the Greek word , "twisted, curved". A "filled-in" helix – for example, a "spiral" (helical) ramp – is a surface called a '' helicoid''. Properties and types The pitch of a helix is the height of one complete helix turn, measured parallel to the axis of the helix. A double helix consists of two (typically congruent) helices with the same axis, differing by a translation along the axis. A circular helix (i.e. one with constant radius) has constant band curvature and constant torsion. The slope of a circular helix is commonly defined as the ratio of the circumference of the circular cylinder that it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guinness Book Of World Records
''Guinness World Records'', known from its inception in 1955 until 1999 as ''The Guinness Book of Records'' and in previous United States editions as ''The Guinness Book of World Records'', is a British reference book published annually, listing world records both of human achievements and the extremes of the natural world. Sir Hugh Beaver created the concept, and twin brothers Norris and Ross McWhirter co-founded the book in London in August 1955. The first edition topped the bestseller list in the United Kingdom by Christmas 1955. The following year the book was launched internationally, and as of the 2025 edition, it is now in its 70th year of publication, published in 100 countries and 40 languages, and maintains over 53,000 records in its database. The international franchise has extended beyond print to include television series and museums. The popularity of the franchise has resulted in ''Guinness World Records'' becoming the primary international source for catal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YouTube
YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in San Bruno, California, it is the second-most-visited website in the world, after Google Search. In January 2024, YouTube had more than 2.7billion monthly active users, who collectively watched more than one billion hours of videos every day. , videos were being uploaded to the platform at a rate of more than 500 hours of content per minute, and , there were approximately 14.8billion videos in total. On November 13, 2006, YouTube was purchased by Google for $1.65 billion (equivalent to $ billion in ). Google expanded YouTube's business model of generating revenue from advertisements alone, to offering paid content such as movies and exclusive content produced by and for YouTube. It also offers YouTube Premium, a paid subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States's civil list of government space agencies, space program, aeronautics research and outer space, space research. National Aeronautics and Space Act, Established in 1958, it succeeded the National Advisory Committee for Aeronautics (NACA) to give the American space development effort a distinct civilian orientation, emphasizing peaceful applications in space science. It has since led most of America's space exploration programs, including Project Mercury, Project Gemini, the 1968–1972 Apollo program missions, the Skylab space station, and the Space Shuttle. Currently, NASA supports the International Space Station (ISS) along with the Commercial Crew Program and oversees the development of the Orion (spacecraft), Orion spacecraft and the Sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phthalate
Phthalates ( ), or phthalate esters, are esters of phthalic acid. They are mainly used as plasticizers, i.e., substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used primarily to soften polyvinyl chloride (PVC). While phthalates are commonly used as plasticizers, not all plasticizers are phthalates. The two terms are specific, unique, and not used interchangeably. Lower-molecular-weight phthalates are typically replaced in many products in the United States, Canada, and European Union over health concerns. They are being replaced by higher molecular-weight phthalates as well as non-phthalic plasticizers. Phthalates are commonly ingested in small quantities via the diet. One of the most commonly known phthalates is bis(2-ethylhexyl) phthalate (DEHP). In many countries, DEHP is regulated as a toxin, and is banned from use in broad categories of consumer goods, such as cosmetics, children's toys, medical devices, and fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polycarbonate
Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate ester, carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, toughness, tough materials, and some grades are optically transparent. They are easily worked, injection molding, molded, and thermoforming, thermoformed. Because of these properties, polycarbonates find many applications. Polycarbonates do not have a unique resin identification code, resin identification code (RIC) and are identified as "Other", 7 on the RIC list. Products made from polycarbonate can contain the precursor monomer bisphenol A (BPA). Structure Carbonate esters have planar OC(OC)2 cores, which confer rigidity. The unique O=C bond is short (1.173 Å in the depicted example), while the C-O bonds are more ether-like (the bond distances of 1.326 Å for the example depicted). Polycarbonates received their name because they are polymers containing carbonate ester, carbonate groups (−O−( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KB Toys
K·B Toys (also known as Kay Bee Toys) was an American chain of mall-based retail toy stores. The company was founded in 1922 as Kaufman Brothers, a wholesale candy store. The company opened a wholesale toy store in 1946, and ended its candy wholesales two years later to emphasize its toy products. Retail sales began during the 1970s, using the name Kay-Bee Toy & Hobby. In 1999, the company operated 1,324 stores across the United States and was the second-largest toy retailer in the U.S., but it began to struggle in the early 21st century, declaring bankruptcy in both 2004 and 2008 before going out of business on February 9, 2009. The company operated 461 stores at the time of its closure. International retailer Toys "R" Us acquired the remains of K·B Toys, consisting mainly of its website, trademarks, and intellectual property rights. Strategic Marks, a company that buys and revives defunct brands, purchased the brand in 2016, and planned to open new stores using the name begi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
