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by edvinbesic 4532 days ago
As a European living in America I disagree. The one value of metric vs imperial is that you (for the most part) don't have to do any math when converting between units.

If I have 1.73 miles, I have to do the math to figure out how many feet that is, 1.73*5280~=9134, which is not something that's easy for me to do in my head.

However, 1.73 km is 1730 meters, which is way easier (at least for me, but that might be my bias).

4 comments

No, you're absolutely right. Thing is, most of the time, when dealing with miles, I don't care how many feet it is. Any distance measured in miles is sufficiently large that its equivalent in feet is largely irrelevant. I suppose it's nice to know that 1.73 km is 1730 meters, but either way, it's a medium-long walk. If I needed to convert all the time ( I suspect this it's really only when using compound units like pound-feet ), that is where I find metric more useful.

Also, I haven't read GP's post, but I find Fahrenheit degrees easier to work with primarily because they're smaller; differences in temperature are easier to express in whole numbers.

Gallons, cups, tablespoons, quarts can go DIAF; I have to convert between these all the time, and it drives me batty!

I live in a country with metric system. We use different units of measurement interchangeably because it's easy to do so and we have gotten used to it. I am 1.74m or 174cm tall. The bus stop is 500m or half a kilometer away from my home, etc. While nobody converts 250km to meters, when the value is closer to one, both units of measurement are equally useful and equally used.

Also all physics and engineering formula are designed to get and return metric values. When I see K = 0.5mv^2, I know v is supposed to be m/s and m is in kilograms and the result would be in Joules. If it's E = m*c^2, the same thing could be inferred about it.

I'm curios with all different units of measurement, how do you know when to use which. Is there a convention to always e.g. use ft/s or is it different in each formula?

Something I never thought about is that there are differences between metric countries too in usage.

E.g. in italy you refer to a glass of 200ml, 100 grams of pasta and two hectograms of parmigiano, while in hungary they routinely use deciliters and decagrams, which I'd never seen outside of school.

And the beauty is that you are still able to easily convert it to the type you are used to. I, as a Belgian, might blink once when you use hectogram, but it is trivial to convert it to what I am more used to (say kg or g).
And as ward has pointed out, it is so easy to convert between them.

On the other hand I don't understand for examples why in the US they still use measures like "cup", "oz" "pint" in cooking. Should I buy a specifically sized "cup" to cook a us recipe? :)

By watching UK television it seems that even they are using kilograms, liters and also Celsius for oven temperature, and some weeks ago there was a UK famous baker talking with some US guest and saying almost the same thing.

disclaimer: I'm Italian

This is exactly why metric is so powerful: I also have no inherent concept of a deciliter or decagram, but I can convert to my understood liter and kilogram in moments.
Even more crazy when dealing with it as an angular unit as Minute of Arc.

Historically: 1 Minute of Great Arc = 1 Nautical Mile

Great Arc = Earth circumference

1 Minute of Great Arc = Great Arc / (360 * 60)

Fun Fact:

Earth Circumference = 4 times great circle distance Pole to Equator historically defined as 10000km or 10 Million Meters (They were that serious about being decimal)

That also explains why the earth radius can still approximately be expressed as 10000km/(π/2) = 6366.2km (just 4.8km off the current mean radius defintion of 6371 km)

http://en.wikipedia.org/wiki/Nautical_mile#History

A funny rant on imperial units you might find amusing.

https://www.youtube.com/watch?v=r7x-RGfd0Yk

Cups are nice because it promotes a "feel" for cooking rather than treating it as a science where the recipe must be followed exactly.
But it's much easier and quicker to simply weigh your ingredients on a digital scale. Step into a professional kitchen and you'll never see anyone using measuring spoons or cups...

Not to mention, having everything in metric and by weight allows you to easily figure out ratios of ingredients, making scaling recipes much easier and quicker.

The usefulness of cups comes from the fact that you create your own home unit depending what you need eith out needing to weight anything. It's just giving proportions, you can use a small cup for one portion size, or a big kettle for a battalion.
In a professional kitchen, scales are mainly used for baking.

On "the line" where food is cooked, measurements are mainly by hand and by eye.

I know how it's done, I used to be a chef, at higher end restaurants than most people will ever eat at.

Yes, during service you're not busting out scales, and a lot of things aren't precisely measured. But anything where precision is necessary, you weigh it. Where it isn't, you don't.

Good luck ever finding a cup measure, or a measuring teaspoon in a professional kitchen though...

>Good luck ever finding a cup measure, or a measuring teaspoon in a professional kitchen though...

In which case, it matters little if you use metric or not...

Baking is actually science-like and needs to be done with precision while cooking is much more about having a feel for the ingredients and tastes.
It's really just the 3 teaspoons in a tablespoon that is annoying to remember. All of the others are just 2 or 4 of the one below it. A week and a restaurant and they start becoming quite natural.
And now that I think of it, Aussie tablespoons are 4 teaspoons (20ml), where US tablespoons are 3 (15ml)
Peter piper picked a peck of pickled peppers.

Thank goodness no one seems to use Pecks / Bushels / Dry Gallons (the dry volume versions of Pints / Quarts / Wet Gallons). The only time I ever hear of "Pecks" is in the Tongue Twister.

For some reason, I get confused between 8 ounces in a cup and 16 in a pound. But a scale will measure in grams just fine, do I tend to prefer that.
>If I have 1.73 miles, I have to do the math to figure out how many feet that is, 1.73*5280~=9134, which is not something that's easy for me to do in my head.

How often do you need to do this in reality? Most people in their day-to-day have no need to these conversions.

you should also consider the extensibility of the metric system as well. Any unit when has a kilo prefix is understood to be x1000 even if you are not familiar with the original quantity. kJ is kilo joules, km is kilo meters. I have no idea how this is handled in your non-metric system is but this property of the SI system definitely makes it much more extensible. you immediately get a sense of the ratio of different metrics. for example consider the ratios of miles/feet ??? feet/inch ??? (I have no idea) compared to kilometers/meters meters/millimeters... this makes it possible to define a metric for a quantity ( meters for distance for example ) and represent all the related quantities easily without having to define a new name for a constant multiple of that quantity.

of course perception of a metric also plays a tremendous role here. I don't have a 'feel' for how long it is 12-feet for example but I can eye-ball a distance and tell how many meters it is pretty accurately. I guess this perception is the main issue that prevents imperial system to be abandoned in favor of SI - people are too much used to it.

I also hate the left driving lane of UK btw. It screws up with my head every time I rent a car in London...

stupid metric-ism ;)

Whereas quite often you'll need to know how long it’s going to take to drive to a city 90 miles away, and it's quite convenient to use the "1 mile ~= 1 minute" approximation to estimate that it'll take 90 minutes.
And this is where metric really shines: at Autobahn speed (130 kph), 90 miles is only some 66 minutes -- 24 minutes saved over imperial. :)
Finally, a convincing argument for the metric system! It will shorten our commutes!
The worst aspect is the real cost of interacting with both metric and imperial systems in America. Those costs manifest themselves in things like the crash of the Mars Climate Orbiter, or closer to home, the fact that I have to have both metric and standard wrench sets at home sitting in my garage to work on a range of projects.
Wait... you're comparing feet to meters. When you should be comparing meters to yards. 1.73 miles * 1760 yards.
Sorry, I wasn't trying to compare units, and the whole example is a bit contrived tbh. The point was simply that in the metric system, when converting between units, all you need to do is move the decimal point, no math required.

This doesn't mean metric is more accurate over imperial, it just means that on a day-to-day, conversion is easier. Also, you can work out the relationship of units simply by their name.

deci = tenth, so decimeters means there is ten of them in one meter. deciliters means ten in one liter. so on and so forth. centi = hundred... milli = thousand...

etc.