Actual poster from 1917 that made me laugh. A lot.

Also, those motherfuckers are measuring the weight of those balls in kilograms, aren’t they?

  • Luccus@feddit.org
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    4 months ago

    1l of (4°C) water weighs 1kg. 1kg (of anything) is 1000g. 1g of water is 1cm³. Stack 1000 1cm³ blocks to get a 10m high column. This column exerts 100kPa of pressure on its base. To heat it by 1°C requires 1kcal. And 1N would accelerate it by 1m/s every second.

    I’ve posted this before on my mastodon, and on feddit.de, before the instance was shut down, but I think it’s still a nice showcase how SI units interact with one another.

    The worst thing we have in the metric system is kWh/1000h. It’s just watts, but whoever designed the energy labels thought a bunch of zeros would be funny or something.

    • litron3000@feddit.org
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      4 months ago

      The kWh/1000h does convey more information than just W though. If I buy a fridge and it says 100W I wouldn’t know if that’s its max power draw or average over time. With the 1000h in there it’s pretty clear we are talking about the average.
      Also people who aren’t technically minded might only know “kWh” as that’s what it states on your power bill and they can directly guess what kind of energy bill this fridge might cause.
      So you are technically correct I guess and we all know that’s the best kind of correct.
      We do have worse stuff in the metric system though, kcal is not the same as the SI for energy (J) for example. Also everything involving time gets messy quickly. Nothing compared to the imperial measurements obviously

    • renzev@lemmy.world
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      4 months ago

      I’ve heard that kWh/1000h is used as a power rating for light bulbs, because if they just wrote it as watts, people might confuse it with a brightness rating (e.g. “this LED bulb produces as much light as a 100W incandescent bulb”)