Over here we switched over to metric about the time I was born, so I was lucky enough to grow up with the Metric system. Never even learned about imperial measurements in school. (Although, school rulers had cm on one side and inches on the other, and blank writing books came with conversion tables on the back. Often they still do.)
Older ones, like glass bottles for soft drinks, tend to be Avoirdupois, because there seems not to be compelling reason to change and retool.
I don't understand. How much retooling does it take to print 710 ML on a bottle instead of 24 FL OZ?
and when we teach, for example, that there are 2.54 centimeters in an inch. Almost nobody will ever need to know a conversion to three significant figures, and if they do, they can always look it up.
That's not merely rounded off to three significant digits. That's the
exact conversion. Sure, you could round it off to 2.5, but if the exact conversion is only one extra digit, why round off? Is it demanding too much that the kids remember to put a 4 at the end?
In many ways, also, non-Metric units have specific advantages. In the Fahrenheit system, the range from 0 to 100 seems to be a good range for human survivability in, say, a business suit.
On the other hand, 0 to 30 in Celsius seems to be a good range for continued human
functionality in, say, a business suit.
I also have some problems with metric screw sizes. It has nothing to do with metric units per se; it just seems to me that the standards chosen result in too many threads for the width of the screw, resulting in the use of unnecessarily big screws. Those are pretty minor, though.
Thread pitch and screw size are two different things. The coarse-pitch is better for screwing into wood, but the fine-pitch is better for screwing into sheet metal. It sounds like you've been using fine-pitch screws for wood.
True there is a certain beauty to nice round numbers, and inter-relatedness of different measurements (energy, mass, length etc) but the fact that energy is related to the temperature by heating a gram of water... really, does that actually benefit anyone?
It's not how they derive the unit that matters to the average person, it's how the units convert. For example, let's pick a random amount. Let's say 4.3...
How many fluid ounces in 4.3 gallons? Can you do it in your head? Probably not. (Answer: 29.77 in the US, 37.21 everywhere else.)
But how many milliliters in 4.3 liters? Easy, 4300.
How much room would 4.3 liters take up? 4300 cm
3.
How much would 4.3 liters of water weigh? 4.3kg.
Makes conversion very easy. No calculator required.
Also meter is IMO too large to be useful in everyday measurements. Things like doors, windows, tables, etc. are usually some single-digit in feet, but 0.x or 1.x in meters. When I was a kid growing up in a metric country, I wondered why decimeter is not used more than it is. It seems as convenient as foot, the way meter is not.
A meter is only slightly longer than a yard, so you could make the same argument about yards being too big.
But for most people, cm is a convenient size. The only difference between a centimeter and a decimeter is an extra digit. May as well use cm. The extra digit isn't much of a hassle, and gives a more accurate size without needing a decimal point.
Not many people use plain meters to measure furniture, doors or windows, unless it's a couple of meters long. In the construction/building industry they go one better and give measurements in mm.
A request to Americans. If you insist in using English or imperial (or whatever the name is) measurements, please avoid giving length in feet when posting in this forum. Use yards, a yard is almost 1 meter long and very easy to visualize for those of us wo use the metric system.
I always picture a foot as being about the same length as a standard 30cm ruler.
But if the auto industry had converted over night it would have been real interesting with all those tool sets out there suddenly obsolete.
No, that doesn't make much sense. Unless they happen to send all non-metric cars to the scrap-heap overnight as well.
