Comment Re: composite units conversion, US pigheadedness (Score 1) 623
Simple measures are easy to convert - a simple numerical factor, usually not too hard to find to sufficient precision. No-one has mentioned the hassle it is to convert useful values (constants, heats of combustion, thermal conductances etc) which are composite quantities, from one system to another. You look for a factor to tell you how much heat will flow through your wall, say, and the US books tell you something in (BTU/hr)/(sq.ft . degree F), and an SI list will have J/m^2.s.K . OK, if you are comparing walls with other walls, the task is not hard, all the values are in the same scale, even if they are the ones you are not comfy with, either way round. For calculating anything across disciplines, SI makes life a whole lot easier. (By the way, there are at least 6 different BTU's for a start!) As anyone involved in developing technology will tell you, interdisciplinary regions are where the action is, so why not lubricate understanding by using SI where it really helps?
Miles, gallons, pounds etc are rarely the basis units used for anything composite & important, so they don't often enter into the sort of conversion trickery above. I'm all for keeping sensible measures for daily life. Someone is 5 feet 6 inches, rather than 173 cm; we like to have small absolute values for casual measurement and conversation. Litres/gallons is borderline - we changed over and there is a psychological element to not seeing £3.50 per UK gallon ($5.70 !!)if you can remember thinking that £1.00 was damned expensive!
Shame we had to waste a hundred million dollars (that's some wierd currency, right, like real pounds and pence but smaller?) to get the issue on the air. No doubt there will be the usual US-style fundamentalists on either side, when a very happy middle position is possible and already well-populated - the UK seems to manage, mostly SI but Imperial for 'homebrew' stuff.
As a last tease, when is the US going to drop MM/DD/YY date format - now that one really is dumb, and don't get up on your hind legs to tell me it isn't, 'cos you know that the DD/MM/YY(YY!) order, or its inverse, makes more sense.
Where did the US system come from, anyhow? Was it transfer from "Jan 4th, '02" or similar?
Miles, gallons, pounds etc are rarely the basis units used for anything composite & important, so they don't often enter into the sort of conversion trickery above. I'm all for keeping sensible measures for daily life. Someone is 5 feet 6 inches, rather than 173 cm; we like to have small absolute values for casual measurement and conversation. Litres/gallons is borderline - we changed over and there is a psychological element to not seeing £3.50 per UK gallon ($5.70 !!)if you can remember thinking that £1.00 was damned expensive!
Shame we had to waste a hundred million dollars (that's some wierd currency, right, like real pounds and pence but smaller?) to get the issue on the air. No doubt there will be the usual US-style fundamentalists on either side, when a very happy middle position is possible and already well-populated - the UK seems to manage, mostly SI but Imperial for 'homebrew' stuff.
As a last tease, when is the US going to drop MM/DD/YY date format - now that one really is dumb, and don't get up on your hind legs to tell me it isn't, 'cos you know that the DD/MM/YY(YY!) order, or its inverse, makes more sense.
Where did the US system come from, anyhow? Was it transfer from "Jan 4th, '02" or similar?
