Project Gutenberg on Nostr: The metre is defined as the distance light travels in a vacuum in 1/299,792,458 of a ...
The metre is defined as the distance light travels in a vacuum in 1/299,792,458 of a second #OTD in 1983.
After the 2019 redefinition of the SI base units, this definition was rephrased to include the definition of a second in terms of the caesium frequency Δν_Cs. This series of amendments did not alter the size of the metre significantly, a change of 0.02% from the original value of exactly 40000 km, which also includes improvements in the accuracy of measuring the circumference.
#science
Published at
2023-10-21 09:00:07Event JSON
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"content": "The metre is defined as the distance light travels in a vacuum in 1/299,792,458 of a second #OTD in 1983.\n\nAfter the 2019 redefinition of the SI base units, this definition was rephrased to include the definition of a second in terms of the caesium frequency Δν_Cs. This series of amendments did not alter the size of the metre significantly, a change of 0.02% from the original value of exactly 40000 km, which also includes improvements in the accuracy of measuring the circumference.\n\n#science\n\nhttps://files.mastodon.social/media_attachments/files/111/272/182/653/256/503/original/f90adee57826c8fa.jpg",
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