5 ms·

Yeah, but a pound of water is not a cubic foot. A pint has nothing to do with inches.

ars 10y ago
That has nothing to do with temperature. You can keep metric and use Fahrenheit with very little change. And you got your units wrong anyway: "To heat one cubic centimetre of water up 1°C takes 1 Joule" - you mean 1 calorie, not 1 Joule. Change Celsius to Fahrenheit and only calorie changes, and since it's anyway not part of SI it makes little difference. Joule is the main energy unit, and it's not tied to Celsius at all. I totally get the arguments for metric - except for temperature. For temperature Fahrenheit is the better scale. Look here: https://en.wikipedia.org/wiki/International_System_of_Units#/media/File:SI_base_unit.svg https://en.wikipedia.org/wiki/International_System_of_Units#... And notice how Kelvin stands alone - it's not tied to any other unit. It can be replaced with almost no impact.
- averagewall 10y ago
  A difference in temperature has the same numerical value in both degrees C and K. Often differences in temperature are all we're interested in so C is often interchangeable with K. If you use Fahrenheit, then you lose that easy relationship unless you also use Rankine for absolute temperature. But nobody, not even Americans, has even heard of Rankine so it would be a far bigger challenge to get anyone to use that than just Fahrenheit alone. Perhaps an even more elegant unit for temperature would be thermal energy per degree of freedom per particle, which would be joules in SI. I'm not sure if that's really correct tho.
  - ars 10y ago
    > A difference in temperature has the same numerical value in both degrees C and K. I know, I used them basically interchangeably in my post. > unless you also use Rankine If people used Fahrenheit more often they would use Rankine more often as well (and yes, I was aware of it before this discussion). > which would be joules in SI Joules is a unit of energy, not temperature. You need to multiply by entropy to get temperature. It would be one thing if the unit for temperature was based on the SI units, fine. But it's not - it's completely arbitrary, and since that is the case you might as well use the more usable Fahrenheit. If I were doing it I would redefine it such that 1 joule of energy applied to 1 gram of water = 1 new-degree. (Right now it's 4.2 joules.) That would make the temperature scale less coarse, which is good. Then make absolute zero -1000 new-degrees.
    - averagewall 10y ago
      Isn't temperature an energy scaled by the Boltzmann constant? That means it's proportional to the energy of something. Why not just use that energy directly instead of converting it to another unit? That's what I means about using Joules for temperature - divide kelvins by Boltzmann's constant Why on earth would you make absolute zero anything other than 0? That's the major problem of Fahrenheit and the reason Celsius is not the SI unit. Instead, you could put a human-level temperature at a round number like 1000 new degrees so everyone always has the leading 1 in there for everyday values.
      - ars 10y ago
        > Isn't temperature an energy scaled by the Boltzmann constant? Only for an ideal gas. For all other materials the scale number is different. That's why temperature is a unit of its own, and it not just energy. > Why on earth would you make absolute zero anything other than 0? I want a "human" oriented scale, that is also tied into SI.
- astrodust 10y ago
  Ah, you're right about calorie vs. Joule. That is a bit rough around the edges. > For temperature Fahrenheit is the better scale. Yeah, no. It's a stupid system. It's not even calibrated properly. 100° was supposed to be body temperature. They got it wrong. 0° was the lowest temperature they could measure at the time because that's when mercury froze. That's so useful! I really want to know if the mercury I carry around all the time is going to freeze outside. Meanwhile °C is simple: 0°C is "watch for ice" and 100°C is "water boils" (minus altitude factor). I don't know how you can praise Kelvin and slam Celsius since they're the same "size", it's just that the zero point of Kelvin was set to absolute zero instead of the freezing point of water. °C = °K + 273.15. That's it.
  - ars 10y ago
    > That is a bit rough around the edges. Correct. It would be one thing if Celsius is somehow tied into the rest of the SI units, but it is not, which means we can replace it. > It's not even calibrated properly. Who cares if they got the calibration of Fahrenheit wrong, at the end of the day it's more usable than Celsius for humans. 0 Fahrenheit is the temperature when it's really cold outside, 100 is when it's hot. It doesn't get simpler than that. If you are outside those ranges you need to take special precautions. No, I don't care about mercury either, but I do care to know when it's cold. It's not that hard to remember 32 for ice. With Celsius you need to deal with negative temperatures all the time, and worse, the size of the degrees is too coarse. > 100°C is "water boils" And exactly how often do you need to measure the temperature when water boils? Probably about as often as I freeze mercury. So 100 is a very useless range on Celsius - you are using your "best" numerical range on useless temperatures. On the other hand it's quite common to want to know when it's hot enough that you will sweat. Above 100 (body temperature) you will sweat. Labs and Ovens don't really care about which exact unit, so let them deal with the higher (or lower) numbers - the only time it matters is for ordinary humans checking the weather. > I don't know how you can praise Kelvin and slam Celsius You misread, I did not praise Kelvin, I said we could replace it.
    - kriro 10y ago
      """And exactly how often do you need to measure the temperature when water boils?""" I drink green tea a lot. You pour the water at 70-75 degrees C. It's a lot easier to do the math of how much water you need to add to instantly cool the water from the water boiler down to that range. """Labs and Ovens don't really care about which exact unit, so let them deal with the higher (or lower) numbers - the only time it matters is for ordinary humans checking the weather.""" What? I use temperature more when cooking/BBQing than when checking the weather. """With Celsius you need to deal with negative temperatures all the time""" This is a feature, not a bug. Negative number -> below freezing. """0 Fahrenheit is the temperature when it's really cold outside, 100 is when it's hot. It doesn't get simpler than that. If you are outside those ranges you need to take special precautions.""" I also need to take special precautions within these ranges. Most notably switching between summer/winter tires.
boondaburrah 10y ago
Yeah, but inches are a unit of length and pint is a unit of volume. Therefore a pint is more relevant here. Yeah technically a cubic inch/foot is volume, but it's not the purpose-built one. To be honest, the volume system in US customary is the only one that makes sense. Everything's power-of-two friendly. If we could revise the others to mesh with that idea then we could have one power-of-10 system (metric) and then a power-of-two system.
- astrodust 10y ago
  That's why there's acre-feet! Because gallons aren't good enough.

ars 10y ago

That has nothing to do with temperature. You can keep metric and use Fahrenheit with very little change. And you got your units wrong anyway: "To heat one cubic centimetre of water up 1°C takes 1 Joule" - you mean 1 calorie, not 1 Joule. Change Celsius to Fahrenheit and only calorie changes, and since it's anyway not part of SI it makes little difference. Joule is the main energy unit, and it's not tied to Celsius at all. I totally get the arguments for metric - except for temperature. For temperature Fahrenheit is the better scale. Look here: https://en.wikipedia.org/wiki/International_System_of_Units#/media/File:SI_base_unit.svg https://en.wikipedia.org/wiki/International_System_of_Units#... And notice how Kelvin stands alone - it's not tied to any other unit. It can be replaced with almost no impact.

averagewall 10y ago
A difference in temperature has the same numerical value in both degrees C and K. Often differences in temperature are all we're interested in so C is often interchangeable with K. If you use Fahrenheit, then you lose that easy relationship unless you also use Rankine for absolute temperature. But nobody, not even Americans, has even heard of Rankine so it would be a far bigger challenge to get anyone to use that than just Fahrenheit alone. Perhaps an even more elegant unit for temperature would be thermal energy per degree of freedom per particle, which would be joules in SI. I'm not sure if that's really correct tho.
- ars 10y ago
  > A difference in temperature has the same numerical value in both degrees C and K. I know, I used them basically interchangeably in my post. > unless you also use Rankine If people used Fahrenheit more often they would use Rankine more often as well (and yes, I was aware of it before this discussion). > which would be joules in SI Joules is a unit of energy, not temperature. You need to multiply by entropy to get temperature. It would be one thing if the unit for temperature was based on the SI units, fine. But it's not - it's completely arbitrary, and since that is the case you might as well use the more usable Fahrenheit. If I were doing it I would redefine it such that 1 joule of energy applied to 1 gram of water = 1 new-degree. (Right now it's 4.2 joules.) That would make the temperature scale less coarse, which is good. Then make absolute zero -1000 new-degrees.
  - averagewall 10y ago
    Isn't temperature an energy scaled by the Boltzmann constant? That means it's proportional to the energy of something. Why not just use that energy directly instead of converting it to another unit? That's what I means about using Joules for temperature - divide kelvins by Boltzmann's constant Why on earth would you make absolute zero anything other than 0? That's the major problem of Fahrenheit and the reason Celsius is not the SI unit. Instead, you could put a human-level temperature at a round number like 1000 new degrees so everyone always has the leading 1 in there for everyday values.
    - ars 10y ago
      > Isn't temperature an energy scaled by the Boltzmann constant? Only for an ideal gas. For all other materials the scale number is different. That's why temperature is a unit of its own, and it not just energy. > Why on earth would you make absolute zero anything other than 0? I want a "human" oriented scale, that is also tied into SI.
astrodust 10y ago
Ah, you're right about calorie vs. Joule. That is a bit rough around the edges. > For temperature Fahrenheit is the better scale. Yeah, no. It's a stupid system. It's not even calibrated properly. 100° was supposed to be body temperature. They got it wrong. 0° was the lowest temperature they could measure at the time because that's when mercury froze. That's so useful! I really want to know if the mercury I carry around all the time is going to freeze outside. Meanwhile °C is simple: 0°C is "watch for ice" and 100°C is "water boils" (minus altitude factor). I don't know how you can praise Kelvin and slam Celsius since they're the same "size", it's just that the zero point of Kelvin was set to absolute zero instead of the freezing point of water. °C = °K + 273.15. That's it.
- ars 10y ago
  > That is a bit rough around the edges. Correct. It would be one thing if Celsius is somehow tied into the rest of the SI units, but it is not, which means we can replace it. > It's not even calibrated properly. Who cares if they got the calibration of Fahrenheit wrong, at the end of the day it's more usable than Celsius for humans. 0 Fahrenheit is the temperature when it's really cold outside, 100 is when it's hot. It doesn't get simpler than that. If you are outside those ranges you need to take special precautions. No, I don't care about mercury either, but I do care to know when it's cold. It's not that hard to remember 32 for ice. With Celsius you need to deal with negative temperatures all the time, and worse, the size of the degrees is too coarse. > 100°C is "water boils" And exactly how often do you need to measure the temperature when water boils? Probably about as often as I freeze mercury. So 100 is a very useless range on Celsius - you are using your "best" numerical range on useless temperatures. On the other hand it's quite common to want to know when it's hot enough that you will sweat. Above 100 (body temperature) you will sweat. Labs and Ovens don't really care about which exact unit, so let them deal with the higher (or lower) numbers - the only time it matters is for ordinary humans checking the weather. > I don't know how you can praise Kelvin and slam Celsius You misread, I did not praise Kelvin, I said we could replace it.
  - kriro 10y ago
    """And exactly how often do you need to measure the temperature when water boils?""" I drink green tea a lot. You pour the water at 70-75 degrees C. It's a lot easier to do the math of how much water you need to add to instantly cool the water from the water boiler down to that range. """Labs and Ovens don't really care about which exact unit, so let them deal with the higher (or lower) numbers - the only time it matters is for ordinary humans checking the weather.""" What? I use temperature more when cooking/BBQing than when checking the weather. """With Celsius you need to deal with negative temperatures all the time""" This is a feature, not a bug. Negative number -> below freezing. """0 Fahrenheit is the temperature when it's really cold outside, 100 is when it's hot. It doesn't get simpler than that. If you are outside those ranges you need to take special precautions.""" I also need to take special precautions within these ranges. Most notably switching between summer/winter tires.

boondaburrah 10y ago

Yeah, but inches are a unit of length and pint is a unit of volume. Therefore a pint is more relevant here. Yeah technically a cubic inch/foot is volume, but it's not the purpose-built one. To be honest, the volume system in US customary is the only one that makes sense. Everything's power-of-two friendly. If we could revise the others to mesh with that idea then we could have one power-of-10 system (metric) and then a power-of-two system.

astrodust 10y ago
That's why there's acre-feet! Because gallons aren't good enough.