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Comment on Why a ton, and not a megagram?

A mass of a million kg should be 1 gigagram or 1 kilotonne. Not 1000t. (Edit: And not a kilotonne either, rather a mega-kilogram.)

The good thing: All of them are correct. The SI system actually does not care if you throw around extra zeros, so 1000t is fine. It is actually better to stay in the same SI prefix and just use larger numbers to make list entries easier comparable. Just imagine some ship shop would list it’s smaller offers in Mg and then switch to Gg for larger ships.

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rufus@discuss.tchncs.de ⁨1⁩ ⁨year⁩ ago
Hmm, halfway…

If you take the context away: When you learn that in school, it’s marked as a mistake if you write 10 000m. You should have converted that into 10km to get a perfect score.

But there are certainly contexts where it makes sense to stay with one prefix. For example if you write things into a table.

I’m not sure if it’s necessarily the case for comparing stuff… It’s kind of rare that you have things that are a factor of 10000 or a million apart, so it’s kind of difficult for me to find examples. But I have capacitors that are 470uF or 22pF and resistors that are 220 Ohm or a Mega-Ohm or 150kOhm. I know how to handle that and switch between all of them. So people do switch and that’s kind of the point of having those prefixes. If I type it into my calculator I simply use the key to type it in in scientific notation and once again so it gives me the closest power of ten. I forgot the name of that key. ‘E’ or ‘ENG’.

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- Treczoks@lemmy.world ⁨1⁩ ⁨year⁩ ago
  
  If you take the context away: When you learn that in school, it’s pointed out as a mistake if you write 10 000m. You should have converted that into 10km to get a perfect score.
  
  Only if this was explicitly demanded. If the teacher doesn’t, and then claim 10000m is “wrong”, the teacher is wrong.
  
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  - rufus@discuss.tchncs.de ⁨1⁩ ⁨year⁩ ago
    I think I had a strict maths teacher. But they told us upfront how to convert units and how to do the rounding. So there were no ambiguities.
    
    But I’ve also come to the conclusion that humans can handle numbers up to the ten or hundred thousands as well. We mostly do that instead of converting past kilo. And even textbooks say the sun is on average 150 million kilometers away.
    
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