Lightboxes
Carrito
alb3817283

National Standard of Mass, Kilogram No. 20

This platinum-iridium cylinder at the National Bureau of Standards is the primary standard kilogram for all metric measurements of mass in this country. It was furnished to the US by the International Bureau of Weights and Measures in accordance with the metric treaty of 1875. Recomparison with the international standard in 1937 showed that the US standard had changed by only one part in 50 million during approximately 50 years. Known as Kilogram No. 20, it is 39mm in diameter and 39mm high, and is made of an alloy containing 90% platinum and 10% iridium.
Compartir
pinterestPinterest
twitterTwitter
facebookFacebook
emailEmail

Añadir a otro lightbox

Añadir a otro lightbox
add to lightbox print share
¿Ya tienes cuenta? Iniciar sesión
¿No tienes cuenta? Regístrate
Compra esta imagen
Cargando...
Título:
National Standard of Mass, Kilogram No. 20
Descripción: Ver traducción automática
This platinum-iridium cylinder at the National Bureau of Standards is the primary standard kilogram for all metric measurements of mass in this country. It was furnished to the US by the International Bureau of Weights and Measures in accordance with the metric treaty of 1875. Recomparison with the international standard in 1937 showed that the US standard had changed by only one part in 50 million during approximately 50 years. Known as Kilogram No. 20, it is 39mm in diameter and 39mm high, and is made of an alloy containing 90% platinum and 10% iridium.
Personas:
Crédito:
Album / Science Source / Omikron
Autorizaciones:
Modelo: No - Propiedad: No
¿Preguntas relacionadas con los derechos?
Tamaño imagen:
3167 x 2550 px | 23.1 MB
Tamaño impresión:
26.8 x 21.6 cm | 10.6 x 8.5 in (300 dpi)
Palabras clave: