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The American Kilogram
- Published_at:2017-05-10
- Category:Education
- Channel:Veritasium
- tags: veritasium science physics metric USA america metric system weight mass kg kilogram K20 IPK mass standard definition SI units metrication unit conversion weigh international prototype kilogram measurement standards units imperial pounds pound ounce ounces grams density kilograms calibrate calibration
- description: The US signed the metre convention and bases all customary units on SI standards. As an aside, the Utah constitution from 1895 required the metric system to be taught in schools. This requirement was repealed in 1987. ¯\_(ツ)_/¯ Huge thanks to NIST, Ben Stein and Patrick Abbott. https://www.nist.gov/ https://www.nist.gov/pml/weights-and-measures/si-units-mass Special thanks to Patreon Supporters: Tony Fadell, Donal Botkin, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen Back in 1875 The US signed the Metre Convention, which basically committed the country to use the metric system. In return, French scientists sent two platinum-iridium cylinders that weigh 1kg to the US in 1889 (known by their designations K4 and K20 from a set of 40 identical objects that were produced and sent around the world). So even though everything you see and buy in the US is usually reported in pounds, all weights are traceable back to the K20 kilogram (by applying a conversion factor to get to pounds). When I was in DC a few weeks ago, I visited the National Institute of Standards and Technology (NIST) and got up close with K20, which is still kept there and used to calibrate all mass standards in this country. I thought it was pretty cool. Edited by Bill Connor
| ranked in date | views | likes | Comments | ranked in country (#position) |
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| 2017-05-11 | 254,831 | 17,761 | 2,263 |
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