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1.2 Å (feddit.org)
submitted 7 months ago by to c/science_memes@mander.xyz
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[–] 10 points 7 months ago (3 children)

EM = electromagnetic? Å = a Swedish letter? What am I missing?

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  • [–] 22 points 7 months ago (2 children)

    I think this is referring to electron microscopy, and å is a unit for 10^-10^ meters. Electron microscopy can be very noisy and it is hard to distinguish objects

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  • [–] 2 points 7 months ago (1 child)

    Angstroms hurt my brain. A $10^{-10}$ of a metre, but not a nanometre or a picometre. Just...why?

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  • [–] 1 point 7 months ago*

    ... However, they soon realized that the definition of the metre at the time, based on a material artifact, was not accurate enough for their work. So, around 1907 they defined their own unit of length, which they called "Ångström", based on the wavelength of a specific spectral line. It was only in 1960, when the metre was redefined in the same way, that the angstrom became again equal to 10^10 metre. Wikipedia

    Edit: also some atoms are about 1 angstrom in size, so it's convenient, I guess..

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  • [–] 15 points 7 months ago* (last edited 7 months ago) (1 child)

    Electron Microscopy. Often used to see very small structures at high resolution. So 1.2 Å is 1.2 angstrom, or 0.12 nm.

    Edit: I should add that often at really high magnification, there is a lot of noise, so the joke is that non EM people would just see static. Not too far from the truth. Practice helps seeing the patterns!

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  • [–] 2 points 7 months ago (2 children)

    That symbol means Armstrongs, but that's all I know

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