xkcd #3106: Farads

Title text:

‘This HAZMAT container contains radioactive material with activity of one becquerel.’ ‘So, like, a single banana slice?’

Transcript:

[Cueball holds a stick while talking with Megan and White Hat.]
Cueball: This stick is one meter long.
Megan: Cool.
White Hat: That’s a nice stick.

[Cueball holds a smallish rock.]
Cueball: This rock weighs one pound.
Megan: I’d believe it.
White Hat: Looks like a normal rock.

[Cueball holds a small battery.]
Cueball: This battery is one volt.
Megan: Seems fine.
White Hat: Might need a recharge.

[Cueball holds a capacitor while Megan and White Hat panic.]
Cueball: This capacitor is one farad.
Megan: Aaaaa! Be careful!!
White Hat: Put it down!!

Source: https://xkcd.com/3106/

explainxkcd for #3106

  • Treczoks@lemmy.world
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    1 day ago

    Only criticism is the use of non-metric weight units when everything else is SI-based.

    • Captain Aggravated@sh.itjust.works
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      15 hours ago

      The joke wouldn’t have worked as well.

      A gram is actually a pretty small unit of weight, and the joke relies on the base units. It’s actually a weird little abberation in the metric system that the “base” unit is considered the kilo gram. so a 1 gram rock would be a little pebble, strangely small.

    • palordrolap@fedia.io
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      1 day ago

      Wikipedia currently says:

      the international avoirdupois pound, […] is legally* defined as exactly 0.45359237 kilograms

      So, technically, a pound is a metric weight, only a niche one whose use may or may not be permitted by local regulations.

      Similar is true* of the inch, which is defined as precisely 25.4 millimetres.

      * The US, UK and a handful of others collectively signed this into their respective laws in 1959. You might think we don’t use the pound in the UK any more but it still shows up often in informal situations. Ditto inches and feet.

      • dellish@lemmy.world
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        17 hours ago

        That’s similar to saying “Auf Wiedersehen” translated to English is “until I see you again”, therefore “Auf Wiedersehen” is technically English. Just because there’s a recognised translation to a thing, that doesn’t make it that thing.

        • palordrolap@fedia.io
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          16 hours ago

          The other way around maybe, that is, an English word becoming technically foreign because we decide that we are going to write its definition in a different language in the dictionary.

          It wouldn’t make sense to do that though, which kind of breaks the analogy. Unless you count words borrowed wholesale because we didn’t have that word, and those definitions were written in a foreign language first.

          As it is “one pound” now translates exactly to “nought point four five three five nine two three seven kilograms” where it didn’t before 1959. “kilogram” is one of those foreign borrowings.

      • emeralddawn45@lemmy.dbzer0.com
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        19 hours ago

        I would argue that a legally defined conversion to a meter or another metric value does not make a unit metric in and of itself. Those units have to adhere to the system, which is clearly based on decimal values, not just some arbitrary conversion with an absurd precision that was only signed into law to minimize the inconvenience caused by non-standard units.

        • palordrolap@fedia.io
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          17 hours ago

          It’s not a defined conversion, it’s the literal, internationally ratified definition of what those units are. Or maybe “redefinition” ought to be the word there; prior to that definition there were several very similar, roughly equal but ultimately not internationally standardised units in use. And since they were redefined in terms of SI units, they’re technically SI.

          This is one of those “tomatoes are technically fruit, but no-one with good sense would put them in a fruit salad” situations.