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why is the US not Metric

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CatalinaWOW:

--- Quote from: bsfeechannel on November 15, 2019, 03:16:47 am ---

--- Quote ---If it bothers you that much, feel free not to come here and not to use anything we currently make that isn't based on a metric standard.
--- End quote ---

Too late.



--- End quote ---

And here we have the heart of the problem.  While the cost of replacing all of the non-metric street signs in America is trivial, the cost of replacing his brain dead, useless, totally antiquated US sourced products that he bought with beautiful metricated products, or the cost of moving back to some enlightened, forward thinking, economically advantaged part of the world is totally unreasonable.

Pardon me while I shed crocodile tears.

tooki:

--- Quote from: Zero999 on November 15, 2019, 09:09:38 pm ---Changing units on food packaging to metric and insisting commodities are primally sold in metric would be fairly cheap and would have some benefit, but I suspect this is already the case to some degree. I wouldn't be surprised if metric is already found on US food packets, as they export them to metric countries such as Canada and Mexico.

--- End quote ---
Groceries in USA have been labeled with metric (with or without customary alongside it) for at least 30 years now, and metric has been required by law since 1992. The only things without even a metric conversion are things sold by variable weight that are weighed in-store (fresh meat, produce, etc), which will be in lbs (usually with decimals, but sometimes with ounces), and the same with items dispensed in-store by volume.

Similarly, when I was a little kid in USA, product packaging (both food and otherwise) was usually in English only, occasionally with French as well for products sold in Canada, too. But nowadays, practically everything is in English and Spanish, and frequently French as well. (I, for one, like that. Passive language instruction FTW!)

KL27x:
Zero, I calculate for you. The cube root distance of a gallon is 6.136 inches. So a (freedom) gallon is a cube 6.136" per side, or 0.5113 feet, or 155.9mm.

This may be easier to use than mL:pint.

Of course when the numbers get so big or small they are not really relate-able, engineers commonly use cubic feet, or cubic meters or other stuff that is not a liter or a gallon.

Why this 6.136" number is not commonly known? We don't make square measuring cups. We don't make square swimming pools. We don't make square gas tanks.

vk6zgo:

--- Quote from: Zero999 on November 13, 2019, 07:31:07 pm ---
--- Quote from: AG6QR on November 13, 2019, 06:27:30 am ---For those who abhor non-decimal factors in units, why do you put up with our current system of time?  Short of tweaking Earth's orbit, we can't do much about the number of days in the year, but all the subdivisions of a day are entirely up to us to control.   We don't need to follow the Babylonian system of 24, 60, and 60.  We could use centidays and millidays for ordinary timekeeping.  A centiday is 14.4 of our traditional minutes, and a milliday is 1.44 minutes.  Once we made the switch, we'd easily change our habits to make classes, meetings, and TV programs last two to four centidays, cookies bake in one centiday or a bit less, a work day is 33 centidays, etc.
--- End quote ---
Yes time is annoying, but we're stuck with the current definition of the second, which is an SI unit and there are 86.4ks per day, whatever we do. As mentioned above, if we change the second, we have to alter all of the other SI units which depend on it, such as capacitance.

As I said before, it's not so much the different bases which make imperial/customary difficult, but the fact that mass, length, volume are totally different systems. Metric is all one standard international system, with everything being multiples of powers of 10.

Example: we have a cuboid shaped fish tank, 4ft 6in long, 18in wide and 15in high. Calculate how many US gallons of water required to fill it to fill it to a depth of 1ft. I wouldn't have a clue how to figure it out using purely customary units. I'd just convert everything to metric:

An inch = 2.54cm and there are 12 of them in a foot.
l = (4*12+6)*2.54 = 137.16cm
w = 18*2.54 = 45.72cm
d = 12*2.54 = 30.48cm

--- End quote ---
well, the cubic capacity in cubic ft  of the tank is 4.5ft x 1.5ft x 1.25ft.
That isn't what we need though------the water level is only 1.0 ft, so the calculation simplifies to :-
4.5 x 1.5 x 1.0, or 4.5 x 1.5 for a cubic capacity of 6.75 cubic ft.

That's the easy part. ;D
I haven't a clue what the conversion factor between cu ft & US Gallons is.
If I knew that, the whole thing would be done with two calculations. (with the values given, converting to decimal feet is obvious)

Back in the Imperial days, decimal parts of a foot, or whatever, were very commonly used, & well known.

--- Quote ---
A litre is 1000cm3
v = 137.16*45.72*30.48 = 191139cm3 = 191.1L

A US pint is 0.473L and there are 8 of them to the gallon.
191.1/0.473 = 404pt
404/8 = 50.5 so the answer is 50 gallons and 4 pints.

How much does does the water in the tank weigh, under standard conditions?
A litre of water near enough weighs 1kg, so 191.1kg. Oh, then answer needs to be in pounds and ounces?
1lb = 0.454kg
191.1/0.454 = 420.925lb
There are 16 ounces per pound:
0.925*16 = 14.8oz
So 420lb 14.8oz but 421lb is close enough.

I hope I've got that right!

There are conversions from cubic inches to pints and the density of a pint of water, but why bother? It's much easier just to memorise the imperial to metric conversions, which will come in handy sooner or later anyway.

--- End quote ---

forrestc:

--- Quote from: vk6zgo on November 16, 2019, 01:11:32 am ---well, the cubic capacity in cubic ft  of the tank is 4.5ft x 1.5ft x 1.25ft.
That isn't what we need though------the water level is only 1.0 ft, so the calculation simplifies to :-
4.5 x 1.5 x 1.0, or 4.5 x 1.5 for a cubic capacity of 6.75 cubic ft.

That's the easy part. ;D
I haven't a clue what the conversion factor between cu ft & US Gallons is.
If I knew that, the whole thing would be done with two calculations. (with the values given, converting to decimal feet is obvious)

--- End quote ---

Entering the following into google:


--- Quote ---4'6" x 18" x 12" in gallons

--- End quote ---

Results in the following result:


--- Quote ---(4 ' 6 ") x (18 ") x (12 ") =
50.4935065 US gallons

--- End quote ---

Doesn't get much easier than that   :)

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