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The super-slow conversion of the U.S. to metric (2025)

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Re: The super-slow conversion of the U.S. to metric (2025)

#341

Post by nearbuy »

ericmay wrote: post #252
nearbuy wrote: post #216

Earlier quoted context omitted.

I think you're saying that where you live, the weather is usually between 0 and 100°F. Aside from the fact that outdoor temperatures aren't in this range everywhere, we don't only use temperature for weather. 100°F is warm to the touch, not smoking hot. 100°C is boiling hot. You sip tea at 60°C, and brew it at 80° to 100°C depending on the type. You cook chicken to an internal 74°C. A hair dryer blows air around 50°C…

> I think you're saying that where you live, the weather is usually between 0 and 100°F. Well let me clarify, what I was saying is that where everybody lives the temperatures tend to be within that range, which is why I think it's a superior measurement for temperature related to the weather - again just additional clarification which was missing maybe from earlier comments. Once you arrive at the point where you're…

I live in one of the most populated cities in North America. The temperature on Saturday is forecasted to go down to -18°F (feels like -29°F with wind chill). It's not at all unusual for temperatures to be below 0°F in winter in much of the world.

> Once you arrive at the point where you're measuring various things, I'm not sure it matters what scale you use so long as the values align as you expect.

You can't have it both ways. The entire advantage you proposed for Fahrenheit is that the outside temperature is often between 0 and 100. It's a tiny aesthetic advantage that doesn't even work very well because 0°F isn't actually the coldest temperature we get and 100°F isn't the warmest.

You're right it doesn't matter that much if water boils at 100° or 212°. It's just different numbers. But by the same token, it doesn't matter if the warmest weather is about 100°F or 40°C. It's just a different number. At least 0°C and 100°C are actual points that mean something and are relevant to everyday life, while 0°F isn't really anything. As I said before, the weather outside changes more at 0°C than at any other temperature.

Re: The super-slow conversion of the U.S. to metric (2025)

#342

Post by SECProto »

tzs wrote: post #290
SECProto wrote: post #259

Earlier quoted context omitted.

No need to simplify this. (F - 32) / 1.8 = C C * 1.8 + 32 = F I personally find the math just as easy to do accurately. For example, 87F -32/1.8 = 55/1.8 =~30.5C. Compare that to your approximate method, which would give 28.5C, which is just wrong (Maybe I just got really good at this when working a public facing job with a lot of American tourists - they would ask what our celsius temperatures were "in real units",…

For C to F you can often simplify the mental math by doing the multiply by doubling then taking off 10%. E.g., to convert 31℃ to ℉: 31 x 2 = 62. Subtract 6.2 = 55.8. Add 32 = 87.8℉. If you want to round the result to the nearest integer the subtract 10% step is a convenient place: 31 x 2 = 62. Subtract 6 (rounded 6.2) = 56. Add 32 = 88℉.

Yes, doubling then subtracting 10% of the resultant works because that is the same as multiplying by 1.8 :)

When going the other way and dividing, I similarly find it mentally easier to multiply by 10/18 (rather than just divide by 1.8)

Re: The super-slow conversion of the U.S. to metric (2025)

#343

Post by jackvalentine »

ericmay wrote: post #86
JKCalhoun wrote: post #77

"Back when I was a Catholic-school kid in northern Wisconsin, my school lessons briefly focused on the metric system. This was in the late 1970s." Man, the progressive school (Comanche Elementary in Overland Park, Kansas!) must have had a huge impact on my life. In addition to open classrooms (I was in Unit 5, not 4th Grade), team teaching, a focus on experimental science, a circular layout to the school with a sunke…

> Yeah, we went over the Metric System that whole year. I can still sing the "Metric Family" song from the film on metric units ("Kilo", "Milli", etc.). And to my young an impressionable mind, the U.S. was joining the rest of the world "Free World" in a kind of Star-Trek-like casting aside of the old things that divided us—joining each other with a focus on progress, science, space… I’ve always found this peculiar be…

I think you’re confusing warmth and use-ability with familiarity.

Nobody who grew up using the metric system feels it ‘cold’ and yearns for something with more character.

Re: The super-slow conversion of the U.S. to metric (2025)

#344

Post by rconti »

fragmede wrote: post #313
rconti wrote: post #268

Earlier quoted context omitted.

Counterpoint to #1, celsius increments are too large. I laugh every time I see a thermostat in a car or home that needs to have steps like 20, 20.5, 21, 21.5.. :)

How is that a counterpoint to #1? By that same logic, inches are too big an increment so it's hilarious every time fraction of one is used. 15/16ths? lololol!

I agree with your logic, and this is a good reason to use centimeters instead of inches.

Re: The super-slow conversion of the U.S. to metric (2025)

#345

Post by tzs »

jrm4 wrote: post #322
tzs wrote: post #262

Earlier quoted context omitted.

The things that make the metric system superior to prior systems are: • Using a uniform set of prefixes to designate multiples and divisions of the base units. Having one unit of say, volume (the liter), and then using prefixes when we need smaller or larger units is way better than having cups, pints, quarts, gallons, pecks, and many more. • Having those prefixes mean powers of 10. That fits in well with our use of…

What precisely is "better" about that? It's more predictable over -- some things that you don't know how they're going to scale? Again, the general thrust of "imperial" is better -- base your units on "utility of the most people using them the most for real life things" Do whatever you want for distances between stars, but no, walking off a room in "feet" can't be beat.

To pace off something in feet most people actually try to pace in yards and multiply by 3 if they want to express the result in feet. They could just as easily pace in meters.

What is better with metric is the consistent way to name multiples and divisions of the base units.

Metric uses power of 10 prefixes but another power could work fine. Power of 2 for example actually fits well with Imperial volume measurements, where a quart is 1/4 gallon, a pint is 1/2 quart, 1 cup is 1/2 pint, a fluid ounce is 1/8 cup, and a tablespoon is 1/2 a fluid ounce.

Just make some prefixes that mean 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, 1/128, and 1/256 and use those with gallon instead of having separate names for everything, and use the same prefixes with yards when you need a unit smaller than a yard and you'd be off to a good start. Add some prefixes that mean 2x, 4x, 8x, etc too.

Yards and gallons don't have to be the base units. Could be feet and cups or anything else. The key is prefixes to get bigger or smaller units instead of naming those others units, and using the same prefixes across unit types.

Re: The super-slow conversion of the U.S. to metric (2025)

#346

Post by wahern »

nearbuy wrote: post #341
ericmay wrote: post #252

Earlier quoted context omitted.

> I think you're saying that where you live, the weather is usually between 0 and 100°F. Well let me clarify, what I was saying is that where everybody lives the temperatures tend to be within that range, which is why I think it's a superior measurement for temperature related to the weather - again just additional clarification which was missing maybe from earlier comments. Once you arrive at the point where you're…

I live in one of the most populated cities in North America. The temperature on Saturday is forecasted to go down to -18°F (feels like -29°F with wind chill). It's not at all unusual for temperatures to be below 0°F in winter in much of the world. > Once you arrive at the point where you're measuring various things, I'm not sure it matters what scale you use so long as the values align as you expect. You can't have i…

The steelman argument for Farenheit as it is, not necessarily the motivations behind it, has been fleshed out here: http://lethalletham.com/posts/fahrenheit.html

TL;DR: "The remarkable result here is that 0℉ is nearly exactly the 1st percentile of daily lows, and 100℉ is nearly exactly the 99th percentile of daily highs." NB: The context is the continental US.

Re: The super-slow conversion of the U.S. to metric (2025)

#347

Post by MarkusWandel »

nayuki wrote: post #173
ericmay wrote: post #86

Earlier quoted context omitted.

> Yeah, we went over the Metric System that whole year. I can still sing the "Metric Family" song from the film on metric units ("Kilo", "Milli", etc.). And to my young an impressionable mind, the U.S. was joining the rest of the world "Free World" in a kind of Star-Trek-like casting aside of the old things that divided us—joining each other with a focus on progress, science, space… I’ve always found this peculiar be…

> I find the imperial system fits in better with that warmth of humanity Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless names and numbers to memorize compared to kilo = 1000, milli = 0.001. > in favor of cultural uniqueness and fun over conformity You're writing in impeccable English. As we know, English is an international language and most definitel…

Here in Canada, my family ran a fishing camp with a lot of US customers. I was talking with one of them about metric vs. US units and to demonstrate I said how about this: How many gallons in a cubic mile? And he was able to work it out in his head, and pretty quickly too. Whoa. The point I was trying to make that is than in metric (say, liters per cubic kilometer) you just need to get the number of zeroes right, but you can't argue with results.

Re: The super-slow conversion of the U.S. to metric (2025)

#348

Post by MarkusWandel »

ahmeneeroe-v2 wrote: post #223
nayuki wrote: post #173

Earlier quoted context omitted.

> I find the imperial system fits in better with that warmth of humanity Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless names and numbers to memorize compared to kilo = 1000, milli = 0.001. > in favor of cultural uniqueness and fun over conformity You're writing in impeccable English. As we know, English is an international language and most definitel…

I enjoy the warmth of the distance light travels in a vacuum in 1/299,792,458 of a second, or as me and my friends call it: a Meter.

Handily enough the speed of light is about a foot per nanosecond, give or take. A nanosecond doesn't sound like much, unless you start to work out, for example, how many bits are inside your 40Gbps USB-C cable at the moment (they do travel at less than the speed of light).

Re: The super-slow conversion of the U.S. to metric (2025)

#349

Post by MarkusWandel »

nayuki wrote: post #233
ahmeneeroe-v2 wrote: post #223

Earlier quoted context omitted.

I enjoy the warmth of the distance light travels in a vacuum in 1/299,792,458 of a second, or as me and my friends call it: a Meter.

For those who don't know: The original definition of a metre is 1/40 000 000th of a full circle of longitude of Earth. That was considered not accurate enough, so it was redefined as the length of a certain metallic bar kept in Paris. Then it was defined in terms of wavelengths of krypton light. Finally, it was redefined in relation to the speed of light. But each time the metre was redefined, the new definition was…

And then there are short vs. long tons (neither of which is a metric tonne)... nautical vs. statute miles... troy vs. regular vs. fluid ounces...

Re: The super-slow conversion of the U.S. to metric (2025)

#350

Post by mturmon »

JKCalhoun wrote: post #303
mturmon wrote: post #225

Earlier quoted context omitted.

Katherine Carpenter Elementary, OP, KS for me, in the same era -- just a couple miles from your school. I share some of the same disappointment, especially going back and noticing disinvestment in the schools, which were one of the gems of the area.

Shawnee Mission was a gem of the Midwest. I was told that only California had better schools (whosaidthat?). (And then of course Prop 13 came along and impaled California.)

My son went to LA-area and LAUSD schools, and the echo of that same commitment from those years in California was still faintly detectable in the 2010s, highly attenuated by Prop 13, as you mention.
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