SI Units and multipliers
Discussion
Mr E said:
The engineer in me wants to point out that the SI unit is the Kg.
So I'm happier with 6000Kg than 6Mg.
Fun fact, the Kg is the only unit that still requires a physical reference. Work is ongoing to to find a less variable measure.
Fair point, but that in itself begs the question of why a unit, isn't.So I'm happier with 6000Kg than 6Mg.
Fun fact, the Kg is the only unit that still requires a physical reference. Work is ongoing to to find a less variable measure.
Plus we also speak in terms of thousands of Kilometres rather than Megametres, so my point stands.
hyperblue said:
There's no real logic to whether we should use kilo/mega etc in relation to the base unit, it's just dictated by common usage. E.g. The mass of most everyday items we encounter is more relatable to refer to in kilograms than megagrams.
I guess we often use the units that are closest to the imperial units - Tons to tonnes, miles to kilometres, metres to yards, etc. etc.
Mr E said:
The engineer in me wants to point out that the SI unit is the Kg.
So I'm happier with 6000Kg than 6Mg.
Fun fact, the Kg is the only unit that still requires a physical reference. Work is ongoing to to find a less variable measure.
The SI unit is 'kg' (small k).So I'm happier with 6000Kg than 6Mg.
Fun fact, the Kg is the only unit that still requires a physical reference. Work is ongoing to to find a less variable measure.
It seems odd that capital K (kappa) hasn't been pressed into service as a multiplier.
Simpo Two said:
motco said:
Simpo Two said:
Sod the French, 'six tons' works for me!
'tonnes' to differentiate from Imperial tons.
Strange that NZ and Oz use km instead of miles; they have no need to.
Kg is the SI unit of mass, not grams (grammes).
Hence when ever practical you should always stay in Kg, when measuring very small quantities this would introduce error because of the limitation of decimal places, hence why you might want to use mg and ug. But there would be no error introduced by expressing larger mass in kg. Ton (Tonne) doesn't mean anything really, you might as well just say "a lot" or a "big bag".
Hence when ever practical you should always stay in Kg, when measuring very small quantities this would introduce error because of the limitation of decimal places, hence why you might want to use mg and ug. But there would be no error introduced by expressing larger mass in kg. Ton (Tonne) doesn't mean anything really, you might as well just say "a lot" or a "big bag".
Edited by FredClogs on Monday 27th March 18:15
Ton is far too ambiguous term to be useful, unless you specifically say Metric Ton, but why not say 1000kg ? You won't find ton used in any trade, technical or industrial context other than as a description for "a lot" or "a big un"
https://en.m.wikipedia.org/wiki/Ton
"The UK Weights and Measures Act 1985 explicitly excluded from use for trade many units and terms, including the ton and the term "metric ton" for "tonne"."
https://en.m.wikipedia.org/wiki/Ton
"The UK Weights and Measures Act 1985 explicitly excluded from use for trade many units and terms, including the ton and the term "metric ton" for "tonne"."
FredClogs said:
Kg is the SI unit of mass, not grams (grammes).
Hence when ever practical you should always stay in Kg, when measuring very small quantities this would introduce error because of the limitation of decimal places, hence why you might want to use mg and ug. But there would be no error introduced by expressing larger mass in kg. Ton (Tonne) doesn't mean anything really, you might as well just say "a lot" or a "big bag".
kg is the SI unit, not Kg.Hence when ever practical you should always stay in Kg, when measuring very small quantities this would introduce error because of the limitation of decimal places, hence why you might want to use mg and ug. But there would be no error introduced by expressing larger mass in kg. Ton (Tonne) doesn't mean anything really, you might as well just say "a lot" or a "big bag".
Edited by FredClogs on Monday 27th March 18:15
FredClogs said:
Ton is far too ambiguous term to be useful, unless you specifically say Metric Ton, but why not say 1000kg ? You won't find ton used in any trade, technical or industrial context other than as a description for "a lot" or "a big un"
https://en.m.wikipedia.org/wiki/Ton
"The UK Weights and Measures Act 1985 explicitly excluded from use for trade many units and terms, including the ton and the term "metric ton" for "tonne"."
Ton != Tonne, and all the quote tells me is that we shouldn't call a Tonne a "metric ton" - although the seppos do.https://en.m.wikipedia.org/wiki/Ton
"The UK Weights and Measures Act 1985 explicitly excluded from use for trade many units and terms, including the ton and the term "metric ton" for "tonne"."
FredClogs said:
Kg is the SI unit of mass, not grams (grammes).
Hence when ever practical you should always stay in Kg, when measuring very small quantities this would introduce error because of the limitation of decimal places, hence why you might want to use mg and ug. But there would be no error introduced by expressing larger mass in kg. Ton (Tonne) doesn't mean anything really, you might as well just say "a lot" or a "big bag".
In my experience, when dealing with very large or very small quantities you always work with the appropriate SI unit. If you are given a value in mm, ug, kph etc., you always convert to a correct SI unit and raise to the appropriate power. In this instance that would be x*10^-3m, x*10^-9kg and any speed in kph can be multiplied by 0.277r to convert to m/s. This removes the need for excessive decimal places. Hence when ever practical you should always stay in Kg, when measuring very small quantities this would introduce error because of the limitation of decimal places, hence why you might want to use mg and ug. But there would be no error introduced by expressing larger mass in kg. Ton (Tonne) doesn't mean anything really, you might as well just say "a lot" or a "big bag".
Edited by FredClogs on Monday 27th March 18:15
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