Fitxer original(708 × 808 píxels, mida del fitxer: 119 Ko, tipus MIME: image/jpeg)

Descripció a Commons

Resum

Descripció
English: A national prototype kilogram standard mass, number K4, kept by the National Institute of Standards and Technology, USA, one of two which serve as the official standard for defining all units of weight and mass in the United States. It is a polished cylinder made of 90% platinum - 10% iridium alloy, 39 mm (1.5 inches) in diameter and 39 mm high. It is an exact copy of the international prototype kilogram kept at the International Bureau of Weights and Measures (Bureau International des Poids et Measures) in Sevres, France It was one of 40 copies which were presented by France in 1884 to different nations as national standards. This copy, K4, serves as a secondary comparison standard, while its twin, K20, serves as the primary standard. In 1884, it differed in mass from the prototype kilogram by about 75 micrograms. Alterations to image: Removed aliasing artifacts (stripes) due to scanning of halftone photo using GIMP FFT filter.
Data
Font National Geographic magazine, Vol. 27, No.1 (January 1915), p. 154, on Google Books. Photo credited to US National Bureau of Standards, now National Institute of Standards and Technology (NIST).
Autor DesconegutUnknown author
Permís
(Com reutilitzar aquest fitxer)
Original work of the US federal government.

Llicència

Public domain
This image is in the public domain in the United States because it is a work of the United States Federal Government, specifically an employee of the National Institute of Standards and Technology, under the terms of Title 17, Chapter 1, Section 105 of the US Code.

English  日本語  македонски  Nederlands  +/−

Llegendes

Afegeix una explicació d'una línia del que representa aquest fitxer
this file represents the kilogram standard

Elements representats en aquest fitxer

representa l'entitat

Historial del fitxer

Cliqueu una data/hora per veure el fitxer tal com era aleshores.

Data/horaMiniaturaDimensionsUsuari/aComentari
actual11:45, 14 gen 2013Miniatura per a la versió del 11:45, 14 gen 2013708 × 808 (119 Ko)ChetvornoHigher resolution image
00:45, 18 feb 2011Miniatura per a la versió del 00:45, 18 feb 2011438 × 499 (52 Ko)Quibik== {{int:filedesc}} == {{Information |Description={{en|A standard kilogram weight kept by the National Institute of Standards and Technology, USA, one of two which serve a

Les 2 pàgines següents utilitzen aquest fitxer:

Ús global del fitxer

Utilització d'aquest fitxer en altres wikis: