Comment on If we took material like rock from space and got it back to Earth enough times, would Earth grow as a planet?

• ccunning@lemmy.world ⁨2⁩ ⁨months⁩ ago

  Isn’t this just a matter of units though?

  Like we could define our own units such that 1 unit of e equals 1 unit of m.

  I have no clue what units that c^2^ formula are actually in 😕

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  • tobogganablaze@lemmus.org ⁨2⁩ ⁨months⁩ ago

    I have no clue what units that c2 formula are actually in 😕

    c is the speed of light, so you can use it by any distance over time unit. But most commonly it’s given as 299 792 458 m/s

    Like we could define our own units such that 1 unit of e equals 1 unit of m.

    So you can’t since m is multiplied by c and c isn’t equal to 1.

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    • Malfeasant@lemmy.world ⁨2⁩ ⁨months⁩ ago

      Actually you can.

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    • ccunning@lemmy.world ⁨2⁩ ⁨months⁩ ago

      Oof - I have to rethink everything I thought I knew about E=mc^2^ 🫠

      I’ve always discounted c^2^ as “just a number” and didn’t consider it was a number of specific units 🫣

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      • tobogganablaze@lemmus.org ⁨2⁩ ⁨months⁩ ago

        I’ve always discounted c2 as “just a number” and didn’t consider it was a number of specific units 🫣

        This is actually very common and I even remember physics teacher basically using the words “don’t worry about it, it’s just a really big number”, because their point was to imaging the big amount of energy you could get from very little mass.

        But I mostly blame old documentaries about atom bombs that just threw in the absolute basics to make what is basically explosion porn.

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