Metric measurements?

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"Fahrenheit is asking Humans how hot it feels."

What are you basing this on, out of interest? The ability to feel 1f difference?
 
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.

Nah, our ability to perceive temperature is not linear anyway. When diving, difference between 6 and 3 celsius water feels much larger than lets say 28 to 31. At least that is how I perceive it :)

Fahrenheit was a genius for inventing a scale which you can calibrate reasonably well without access to purified water or other sophisticated lab equipment not available in his era. The degree is 1/64th of the difference between his calibration points, something that your can recreate without a ruler or tape measure when building your thermometer.
 
I've seen and heard the phrase used many times when discussing temperature scales. But yes, that's the premise behind it.

I know that was not Fahrenheit's intent when he created the scale, it just sort of works out that way.

A: "It's hot"
B: "But it's only 33°C"
A: "Yeah, but it's a warm 33...."

LOL.
 
Nah, our ability to perceive temperature is not linear anyway. When diving, difference between 6 and 3 celsius water feels much larger than lets say 28 to 31. At least that is how I perceive it :)

Very true, because water conducts heat much better than air. I wasn't thinking in the sense of water temp diving, more in regards to weather. But you're right. Yay for thermodynamics! :thumb::rofl3:

Fahrenheit was a genius for inventing a scale which you can calibrate reasonably well without access to purified water or other sophisticated lab equipment not available in his era. The degree is 1/64th of the difference between his calibration points, something that your can recreate without a ruler or tape measure when building your thermometer.

Totally!
 
Fahrenheit was a genius for inventing a scale which you can calibrate reasonably well without access to purified water or other sophisticated lab equipment not available in his era.
But you'd need a human running a fever to calibrate 100F. :wink:

And to calibrate Celsius degrees more "close enough for government work" you need rainwater, a freezer and a stove. Frankly, that doesn't seem like hard-to-get materials or sophisticated lab equipment to me. :)

Regarding the precision of Celsius vs Fahrenheit, I guess it depends on what you're used to. I don't bother much with temperature differences smaller than ~1C/2F in my private life.
 
But you'd need a human running a fever to calibrate 100F. :wink:

It was originally calibrated to 96 F :) A freezer was hard-to-get and beyond sophisticated in 1724 :)

Metric vs imperial, C vs F. It all really depends on what one is used to. And it is really hard to change habits, like I am always disappointed with a 1/2 lb steak but happy with a 250 gram one.
 
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Well, shipbuilding abandoned cubits after Noah's extravaganza! I bet people argued about it! My parents measured their own weight in stones. The UK ran out of stones so went over to kg. I'm 90kg and 1.92m tall but I converted that to 6'4" to keep up with John Wayne.
 
It is a measurement of volume, just like the liter. It is just under the US scuba labeling scheme we label them by effective capacity.

So you know that a HP100 contains about the same amount of gas as a LP100. Where as under the European labeling they would be labeled as 12L and 15L (IIRC) respectively to find out their effective capacity you would need to find the working pressure and multiple that out.
not really all you need to know is your consumption rate. if you are about .6 fuft that is about 15 liters. and if you have a 15 liter tank at 250 bar you have 250 minutes of air. that calculation is much easier than going all the way to cuft and then dividing by consumption rate. with imperial system it is akin to marking your tank with psi = 1 cuft. knowing that you can take any psi and tall time. I think we call that tank factor in the US. yout hp100 would be 34# for the tank factor.
 
I dunno about asking humans about Fahrenheit (or Celsius). This past Dec I was in place with divers from many places. sSome were using dry suits and others Speedos. I was only using a polartec skin and regretting it.
Funny thing was to see the dry suit couple having hot cocoa after their dives to warm up, I was jealous of them. But yeah Fahrenheit probably wasn't planning on that..
 
Even English/standard units there are differences. A gallon? US or imperial. (hint: American cars get lower MPG because the gallon is smaller). Pipe thread, 1/8" pipe thread should be simple enough. No, there is NPT (National Pipe Thread) and BPT (British Pipe Thread). difference is 1 thread per inch. And most of the world runs BPT. Japanese cars will have BPT threads on them to this day.
 
https://www.shearwater.com/products/teric/

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