StrykeSlammerII wrote:Regarding antimatter production: yes the prefix 'a' is used (among others), but the unit of space resources is elsewhere noted to be decatonnes, seemingly based on 1 boost = "1 decatonne into LEO".
This makes antimatter prefixes confusing for everyone
![Rolling Eyes :roll:](./images/smilies/icon_rolleyes.gif)
Used consistently, i.e. if space resource production was written as "210.3 dat + 2.4 dat", and the antimatter as "5.4 ag + 0.11 ag" then, although those prefixes and units are perhaps... well,
alien to many, at least there would be some way to figure out what is meant. ("It's all SI prefixes and units, look them up on Wikipedia.")
Edit: I looked them up on Wikipedia, and realised I'd mixed up d (deci) and da (deca). Fixed now.
![Smile :)](./images/smilies/icon_e_smile.gif)
Unless there's a reason for displaying resource production in decatonnes specifically, perhaps better to use tonnes instead. Or why not Mg?
StrykeSlammerII wrote:I can see how context is required though: would "kmps" be "km * ps" or "km/s"?
At least in this case it couldn't be the former since prefixes are never stacked. I feel the reasons to use / instead of p are mostly 1) it's by definition the correct way to do it according to the standards (see e.g
USMA, linked to by
NIST), and 2) it stands out more than "just another letter" which differentiates it nicely from prefixes and units. So again, it helps with unit analysis, for example.
StrykeSlammerII wrote:When I (personally) go to do unit analysis though, I always write it out longhand. Too many hoops to jump through to get my computer to show nested divisions in a way that is clear to me!
Qalculate is a great tool for "everyday unit analysis"!
![Smile :)](./images/smilies/icon_e_smile.gif)
(And just a great calculator in general.) It can do things like this (calculation of time to heat up 1 kg of water with an electric heater under ideal circumstances):
![Qalculate.png](./download/file.php?id=478&sid=3c6b670f0d11f4ce3bceffcefd165c34)
- Qalculate.png (25.11 KiB) Viewed 3839 times
StrykeSlammerII wrote:Conversion factors are less relevant under SI, but IMO they still apply to time: days and hours (or minutes) are more intuitive than kiloseconds.
True. The dozen is just too practical since it's so easily divisible by integers! By 2, 3, 4, and 6. Great when speaking of time periods. In general, for display (and input) prefixes and conversions are required (but remember that the unit for minute is "min", not "m").
Another example is the degree (angles). While I'm happy with radians, I'm probably in a very small minority.
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)