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The most official water costs $120k a gallon

signoregalilei.com

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Re: The most official water costs $120k a gallon

#111

Post by buildsjets »

foobarian wrote: post #72
buildsjets wrote: post #64

Earlier quoted context omitted.

Truth. I once paid nearly $500 for a set of 17 certified, calibrated wooden pencils, with documentation showing that each one met their rated hardness levels of 9H thru 6B. And for $500, they don't even come with erasers, that is an added-cost option. https://www.gardco.com/product/pencil-hardness-test-kit-astm...

Can I ask why :-) Sounds like an interesting project.

The pencil hardness scale is commonly used to assess paint film hardness by checking what is the softest pencil that can mar the surface when you scratch it with a given force. In this case, we needed to assess whether exposure to a certain chemical degraded the integrity of the paint coating that we were counting on for corrosion protection.

Re: The most official water costs $120k a gallon

#114

Post by kelnos »

Timpanzee wrote: post #56
al_borland wrote: post #27

Earlier quoted context omitted.

This has always been my primary argument in favor of Fahrenheit. It makes sense for humans, which is all a majority of the population really cares about. In addition, it's more granular. Sometimes turning the thermostat up or down by 1C could be too much, where 1F is just right. In science and math, I can see where having round numbers for commonly used temperatures would be useful, but if 0C and 100C are the only pl…

You only think it makes sense for humans because it makes sense for you, where you live the same way you feel changing a thermostat by 1F is perfect but 1C is too much: that’s true for you, not universally. Fahrenheit functionally requires you to be biased in order for it to seem like a good system.

Every non-US thermostat I've seen that works in Celsius is adjustable by half-degrees, so it seems the manufacturers agree with my feeling there...

Re: The most official water costs $120k a gallon

#115

Post by CrazyStat »

kccqzy wrote: post #45
warmdarksea wrote: post #18

Earlier quoted context omitted.

this is actually why i like fahrenheit the most... 0F is "really cold" and 100F is "really hot", whereas in celsius 0C is "kind of cold" and 100C is "uninhabitable". it makes sense for the 0-100 range to be reserved for temperatures frequently encountered in our habitat as humans i think...

That’s a biased view that leads to a scale only convenient for people living in particular latitudes. Now talk to someone living near the equator like Singapore, and 0F is unimaginably cold (even 40F is basically unheard of), and 100F is very hot but not extraordinarily so. Then you talk to someone living close to the arctic and the converse is true. All this talk about 0F to 100F being frequently encountered probabl…

> Now talk to someone living near the equator like Singapore, and 0F is unimaginably cold (even 40F is basically unheard of), and 100F is very hot but not extraordinarily so.

Bad example--Singapore has never had a single 100F day in recorded history. The highest temperature ever recorded was 37C/98.6F. As a small island its climate is greatly moderated by the masses of water around it. It rarely gets above 90F.

The broader point about the 0-100 Fahrenheit scale being convenient for people from a certain climate is correct, of course.

Re: The most official water costs $120k a gallon

#116

Post by kelnos »

al_borland wrote: post #59
Timpanzee wrote: post #56

Earlier quoted context omitted.

You only think it makes sense for humans because it makes sense for you, where you live the same way you feel changing a thermostat by 1F is perfect but 1C is too much: that’s true for you, not universally. Fahrenheit functionally requires you to be biased in order for it to seem like a good system.

It provides greater granularity in the range of human comfort, without descending into decimals. How is that not more useful for day-to-day human usage? 0F is cold, 100F is hot. I experience both of these temperatures outside where I live every year. -20C to 40C seems much more arbitrary as a way to measure the zone humans mostly live in. I would wager that the outdoor and room temperature are an overwhelming majorit…

> 0F is cold, 100F is hot. I experience both of these temperatures outside where I live every year.

This is just your location, and things like this vary around the world a lot. Hell, they vary in the US. To me, where I live (in the US), 0F and 100F aren't really useful as benchmarks; we don't see either of those temperatures here, ever. The normal range is more like 40F-80F (with extremes maybe down to 25F and up to 90F, but those numbers push credibility a bit).

But ok let's look at averages. Do "most humans" (whatever that means) really live within 0F to 100F? That doesn't really pass the smell test for me; there are lots of humans who live in places where it regularly exceeds 100F. And in those places I doubt it gets anywhere near 0F, with many places never getting down to even 20F. There are also lots of places that get warm, but will never see 100F, and seldom see 90F.

It's all super super arbitrary.

Having said that, I still prefer F over C, but I don't pretend there's any rational reason for it: it's just because I grew up with Fahrenheit, and no matter how hard I try, I just can't feel Celsius the same way. I feel like you maybe don't interact with too many people who grew up with Celsius; you'd probably realize they feel the same way about C as you do about F, and that there's no rational reason for it. It's just what you were trained to think and feel in, and it stuck.

Re: The most official water costs $120k a gallon

#117

Post by tedd4u »

cjs_ac wrote: post #6
sudb wrote: post #3

Reminds of me of the "most expensive peanut butter" at ~$2.44/g - sold by NIST, I assume for some sort of peanut butter factory process calibration: https://shop.nist.gov/ccrz__ProductDetails?sku=2387

SRM 2387 pairs well with a cup of ISO 3103. https://en.wikipedia.org/wiki/ISO_3103

"It was produced by ISO Technical Committee 34 (Food products), Sub-Committee 8 (Tea)."

Re: The most official water costs $120k a gallon

#118

Post by kelnos »

al_borland wrote: post #69
masklinn wrote: post #63

Earlier quoted context omitted.

> 0F is cold, 100F is hot. I experience both of these temperatures outside where I live every year. Most people never experience anywhere near 0F in their lives. > -20C to -40C seems much more arbitrary as a way to measure the zone humans mostly live in. The zone most humans live in does not routinely (if ever) get anywhere near -20, to say nothing of -40.

The -40C was a typo, should have been 40C, to mirror the 0F to 100F, rounding a bit to make it less silly. It’s been fixed now. Millions do experience 0F, and it’s ok to not use the full range. At or around 0F is cold, as you move closer or beyond it, it’s cold. As you move closer to or beyond 100F, it’s hot. Most people would likely prefer to never deal with 100F.

Millions -- hundreds of millions, even -- regularly experience -10F and 110F as well, but you've arbitrarily picked 0F-100F, so I guess their experience doesn't matter, because you prefer round numbers?

Re: The most official water costs $120k a gallon

#119

Post by analog31 »

0cf8612b2e1e wrote: post #38
analog31 wrote: post #10

Earlier quoted context omitted.

I think that both the Celsius and Fahrenheit scales are now defined in terms of Kelvin and a formula. Most if not all of the units of measure are no longer related to their history except for an agreement to make the new units match the old ones at some point.

The US is technically metric in that the units are defined in terms of the metric equivalent. A US inch is exactly 2.54cm.

An odd little factoid: A metalworking lathe will usually have a mechanism for cutting screw threads, with a multi-ratio gearbox for linking the rotation of the spindle to the motion of the carriage. For cutting metric threads, you have to change a pair of gears. So there will be a pair of gears with 50 and 127 teeth, which produces the 2.54 ratio. Then you have to look up the correct gearbox settings for each metric thread pitch in the manual. [0]

It's a big royal pain in the arse, and I've never had a machinist agree to turn metric threads on a lathe. They would rather wait a day and order a metric tap or die. Nowadays the CNC lathes just do it auto-magically.

Also, among old bicycles, there are some weird national thread standards that had metric diameters but inch thread pitches, because of machinery imported into countries like Italy and France during reconstruction after WWII.

[0] Edit: Just noticed duplicate comment preceding mine.

Re: The most official water costs $120k a gallon

#120

Post by kelnos »

al_borland wrote: post #57
vagrantJin wrote: post #46

Earlier quoted context omitted.

Celcius is pretty intuitive actually. It takes atmospheric pressure into account, Water is pretty abundant on the surface of the planet, and life kinda depends on it. It's a remarkable substance and quite stable. I dont think theres another substance where we can see all three phases with kitchen appliances and still consume it. Equally good for bathing and drinking. I need steam to clean clothes and cook my food. Us…

With all of those examples, the actual temperature doesn’t really matter. For drinking and bathing, people go by feel. In the kitchen, the freezer makes water freeze, and the stovetop will make it boil into steam, but exact temperatures aren’t really relevant here either. The same goes for ironing clothes, the iron just does it. When I think about where explicit temperatures are needed in the home, the oven and therm…

> For drinking and bathing, people go by feel.

Yes, and people who grew up with Celsius feel in Celsius, and people who grew up with Fahrenheit (like myself) feel in Fahrenheit.

Stop trying to make some sort of determination of what's logical or reasonable here. Neither one is more or less logical than the other for day-to-day layperson use; anyone can "feel best" in any scale if they were taught it at a young age and used solely that scale for the formative years of their lives. Hell, I bet you could make a kid feel in Kelvin if that's all they were exposed to for their childhood. Or in some made-up scale that takes your 0F-100F and compresses it inside 22-35.

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