Ir al contenido

Archivo:Standard kilogram, 2.jpg

Contenido de la página no disponible en otros idiomas.
De Wikipedia, la enciclopedia libre

Ver la imagen en su resolución original (708 × 808 píxeles; tamaño de archivo: 119 kB; tipo MIME: image/jpeg)

Resumen

Descripción
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.
Fecha
Fuente 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 DesconocidoUnknown author
Permiso
(Reutilización de este archivo)
Original work of the US federal government.

Licencia

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.

العربية  English  日本語  македонски  Nederlands  +/−

Leyendas

Añade una explicación corta acerca de lo que representa este archivo
this file represents the kilogram standard

Elementos representados en este archivo

representa a

Historial del archivo

Haz clic sobre una fecha y hora para ver el archivo tal como apareció en ese momento.

Fecha y horaMiniaturaDimensionesUsuarioComentario
actual09:45 14 ene 2013Miniatura de la versión del 09:45 14 ene 2013708 × 808 (119 kB)ChetvornoHigher resolution image
22:45 17 feb 2011Miniatura de la versión del 22:45 17 feb 2011438 × 499 (52 kB)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

La siguiente página usa este archivo:

Uso global del archivo

Las wikis siguientes utilizan este archivo: