Metric measurements?

[RyanT]

And what do you know, fancy kitchens in the U.S., just like tech divers, work in metric, because it's easier and less error prone.

Right?

 

[Ana]

I Temperature is pretty easy: -10C is incredibly cold, 0 is freezing, 10 is chilly, 20 is nice, 30 is warm, 40 is incredibly hot. Though I still don't know what my body temperature is.
.

I came to the US in the early 80's with my kids, a toddler and a baby. Well I brought several big boxes of household stuff, among them the kids body thermometers.
The first visit to the ER was memorable, I can still remember the face of the nurse when I told her my baby had a 42° fever.

 

[drrich2]

I learned metric in school and it was thoroughly reinforced in college, and were all other things equal it'd be the superior system. All other things aren't equal.

I think in imperial as that's what I've made associations with all my life. So if you give me metric units for real world concerns (as opposed to x mg NaCl mixed into y ml H2O = something (been along time since Chemistry coursework), I convert to imperial to 'visualize' it.

An often praised advantage of metric is the base 10 bit; this unit x 10 = that unit, etc... (1 km = 1,000 meters, 1 meter = 100 cm). But in the real world, I don't do many conversions. I'm about 6'1"; I don't convert that to 'just inches' or yards. I don't convert miles to yards or inches. Or my weight in pounds to ounces.

One thing I dislike about metric is the absence of a routinely used equivalent to the foot. A meter is a little more than a yard, and from scuba 10 m = ~ 33 feet. Fine. But for human height, most people are 5 foot something inches tall, or 6 foot something inches tall. I'd give you a blank look if you rattled off somebody's height in cm or meters. For some things a cm is too short and a meter too long. I like the foot.

Seems even the metric people have their base 10 limits; haven't heard any serious proposals to divide the day into 10 metric hours, those into 10 metric minutes, those into 10 metric seconds, etc...

Richard.

 

[Storker]

Seems even the metric people have their base 10 limits; haven't heard any serious proposals to divide the day into 10 metric hours, those into 10 metric minutes, those into 10 metric seconds, etc...

IIRC the French tried that back in the 1790s. Didn't catch on.

 

[wnissen]

One thing I dislike about metric is the absence of a routinely used equivalent to the foot. A meter is a little more than a yard, and from scuba 10 m = ~ 33 feet. Fine. But for human height, most people are 5 foot something inches tall, or 6 foot something inches tall. I'd give you a blank look if you rattled off somebody's height in cm or meters. For some things a cm is too short and a meter too long. I like the foot.

Yep, that is one of the true advantages of customary units. There is research showing that even native metric users are not quite as accurate estimating quantities of mass and volume.

The thing with conversions is that you don't do them unless they're easy. If you have a 9 inch tile and you need to figure out how many you need to span a 15 foot space, you'll probably get out a calculator. But a 20cm tile into 5 meters, that's trivial math.

And units are around a long time. If you buy gas in Puerto Rico, the measure is in liters, but the price is, e.g., $.60 and 7/8ths, not 9/10ths. Yep, the Spanish doubloons, or "pieces of eight" live on in modern-day society.

 

[BRT]

To measure the height of a tire I get a tape measure and measure it.

So long as you already have the tire that kind of works, but not as well as you might think.

 

[BRT]

Being British, born in the mid 60's, I am basically straddled the two systems. For years, weight made no sense to me.

The amusing thing is that I extensively use metric. But, I happy mix and match. Part of that is to annoy either my European friends and American friends.

e.g. its 10 inches, +/- a few millimetres

Interestingly carpentry, although theoretically metric, is actually still imperial. 3x4 inch = 75x100 (with a tolerance allowance). Nails and screws are still 1", 2", 3' (25mm, 50mm, 75mm)

A bunch of "metric" sizes are actually Imperial sizes converted.

 

[Vitesse2l]

When I worked in precision engineering we swapped between metric and imperial without really thinking about it. Microns and thous and coversions between them were easy, especially with digital measuring gear. Occasionally I'd come across a US drawing with tolerances plus or minus a 64th or something. Can't visualise or quickly measure that with a micrometer! There was never enough repetition to get familiar.

 

[taimen]

Yep, that is one of the true advantages of customary units. There is research showing that even native metric users are not quite as accurate estimating quantities of mass and volume.

Would be interesting to see a reference. Very hard to believe for someone who is truly a native metric user. Like grown up in a country where imperial/customary units have not been used at all for more than 150 years. I learned imperial units and their conversions in high school, and they have always felt arbitrary. I happily do the conversions, and don't feel either system is really superior outside science/engineering.
There used to be a customary system in my country a long time ago. While the units were named foot, inch, and so on, the measures were actually vastly different from the imperial units used in the US today. Thus, when we dive a 18th century "100ft" wreck in our waters, that ship has never been 30,48 meters long.
These things are cultural, not optimized for human perception.

But for human height, most people are 5 foot something inches tall, or 6 foot something inches tall. I'd give you a blank look if you rattled off somebody's height in cm or meters. For some things a cm is too short and a meter too long. I like the foot.

That is just because you are grown up with that system. 180 cm is just as easy for average male height. And kids here know exactly how tall is 120 cm and allowed to ride the roller coaster in the amusement park.

 

[D_Fresh]

I'm tied to nautical miles as well, and speed in knots. On the one hand, it's so logical: A distance that relates to latitude. On the other hand, the whole degrees/minutes system starts with the Babylonian assumption that year is 360 days, so a circle is 360 degrees....

Generally I prefer the metric system for calculations. I could go either way on a pressure gauge and depth. But I have to say I prefer rating tanks by their effective volume if normally filled. I can still run the math to figure out consumption based on drop in PSI. When I'm buying a tank, though, I want to know how much air I can normally stuff into it.

This. I also use Nautical Miles and Knots.

But I grew up in the US, learned Imperial with a lot of exposure to Metric. I'm now living in the Philippines, which is mostly metric, except for medical applications.... I can freely change between the two, but actually prefer metric.

I prefer Metric for diving, but can easily switch to Imperial to match a buddy.

EXCEPT with temperature. Yes, the C scale is conveniently divided between water freezing and boiling, but it's less precise. One degree F is is smallest difference in temperature perceivable to the human body.

Kelvin is asking an Atom how hot it feels.

Celcius is asking Water how hot it feels.

Fahrenheit is asking Humans how hot it feels.