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Units

@UnitFact

Units of measurement, constants, dimensional analysis, etc. From @JohnDCook

JohnDCook.com
Joined April 2014
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Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)Photo by Units (@UnitFact)
Why dimensional analysis matters
Image from Units (@UnitFact)
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cron jobs are going through the most epic rebrand
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SI unit names are not capitalized, except for Celsius. Unit abbreviations are capitalized if and only if they units are named after people. So for example, Pascal is the man, pascal is the unit, and Pa is the abbreviation.
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A batman was a traditional unit of weight used in the Ottoman Empire, equal to about 17 pounds.
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The constant G in Newton's law of gravity is only known to between 3 and 4 significant figures. en.wikipedia.org/wiki/Gravit…
Gravitational constant - Wikipedia

Gravitational constant - Wikipedia

en.wikipedia.org
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.@UnitFact will be ending June 14. If you've enjoyed following @UnitFact, I suggest you follow @ScienceTip instead.
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A span is nine inches.
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Converting between loudness units of phon and sone johndcook.com/phon_sone.html
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A warhol is equal to 15 minutes of fame.
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Standard SI prefixes are single Roman letters with two exceptions: the prefix for deca uses two letters, da, and the prefix for micro is μ.
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Units of measure in Middle Earth askmiddlearth.tumblr.com/pos…
Units of Measurement in Middle Earth

Units of Measurement in Middle Earth

There's an appendix to "The Disaster of the Gladden Fields" in The Unfinished Tales that directly addresses linear measurement in Middle Earth. It digresses a bit into a discussion of heights of...

askmiddlearth.tumblr.com
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.@UnitFact will be ending June 14. If you've enjoyed following @UnitFact, I suggest you follow @ScienceTip instead.
Image from Units (@UnitFact)
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An electron volt (eV) is the amount of energy gained by a charge of one electron moved across an electric potential difference of one volt.
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Standard SI prefixes for factors of 10^6 and higher use upper case letters. Smaller factors and fractions use lower case letters.
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Informally, an astronomical unit is the distance from the Earth to the sun. Officially it is 149,597,870,700 meters.
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Leap seconds johndcook.com/blog/2020/02/0…

Leap seconds, Unix time, and TAI time

Leap seconds are not as familiar as leap days. What are they? Why are they necessary? Why are they controversial?

johndcook.com
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The name SI comes from French: Le Système international d'unités.
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.@UnitFact will be ending June 14. If you've enjoyed following @UnitFact, I suggest you follow @ScienceTip instead.
Image from Units (@UnitFact)
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A fortnight is two weeks. It is a contraction of 'fourteen nights.'
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In typography, a pica is 1/6 of an inch, and 12 points to a pica.
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.@UnitFact will be winding down soon. If you've enjoyed following @UnitFact, I suggest you follow @ScienceTip instead.
Image from Units (@UnitFact)
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