Fun fact time, -40F is -40C.
And 575F is 575K
Fahrenheit vs. Celsius vs. Kelvin
Submitted 1 year ago by genfood@feddit.de to science_memes@mander.xyz
https://i.imgur.com/sve2dpO.png
Comments
chaogomu@kbin.social 1 year ago
BeigeAgenda@lemmy.ca 1 year ago
Fahrenheit is a strange scale.
jivemasta@reddthat.com 1 year ago
Fahrenheit makes sense for humans. Most of your day to day climates are in the 0 to 100 scale, and every 10 degrees is a noticeable level change.
- 100 super hot day, approaching unsafe without counter measures
- 90 really hot day, slightly annoying and should take precautions
- 80, hot day, more annoying than anything
- 70, beautiful day, enjoy it
- 60 not to bad, if it’s windy you could be slightly on the cold side
- 50 long sleeves or maybe a hoodie
- 40 definitely a jacket, and hat
- 30 full on coat, scarfe, and hat
- 20 multiple layers of out for a while, maybe double pants
- 10 annoyingly cold, need to start thinking about the safety precautions
- 0 and below, temperature now measured in hold long you can be outside before danger
Celsius makes sense for science stuff because it’s derived from science stuff, so things like calories and energy work with it. But it doesn’t really apply to everyday life as well. So it actually makes sense to use both units for the things the are good at.
ricecake@sh.itjust.works 1 year ago
It’s just designed with a slightly different set of assumptions.
Instead of water freezing and boiling 100° apart, it’s 180° in fahrenheit. That makes it so that they’re on the opposite sides of a temperature gauge, and a degree of rotation of the gauge matches a degree of temperature.
Instead of zero being the freezing point of water under specific conditions, it’s a brine solution whose temperature will stabilize in a way that’s useful for using as a calibration point.Stripped of its context, it’s odd. But it’s not irrational, just no longer consensus as the standard, and as such deprecated.
namingthingsiseasy@programming.dev 1 year ago
And at what temperatures are C and K equal?
chaogomu@kbin.social 1 year ago
Never. They use the same spacing between degrees. The Kelvin scale was derived from the Celsius scale, just placing the 0° at absolute zero rather than at the freezing point of water.
perviouslyiner@lemm.ee 1 year ago
Based on human perception, based on water chemistry, based on physics.
tryptaminev@feddit.de 1 year ago
You’ll be shocked to learn that the distance in Kelvin is also adjusted to water “chemistry”, albeit changing the aggregate state seems more physics to me, since no molceules are reacting with each other.
perviouslyiner@lemm.ee 1 year ago
Thankfully that has been redefined using the Boltzmann constant, so now anyone in the universe can agree on °C and K without needing to measure any Vienna standard ocean water.
Spzi@lemm.ee 1 year ago
You can’t change the aggregate state of a single molecule, or how do you mean that? Excluding plasma.
CookieJarObserver@sh.itjust.works 1 year ago
Nah Kelvin is just on hydrogen perspective
(Kelvin and Celsius are the same scale just with different 0)
rainynight65@feddit.de 1 year ago
Zero Fahrenheit is the freezing point of brine (of a certain concentration). That’s water chemistry.
Originally, 90F was based on the average human body temperature, but that later changed to 96F, which just goes to show how arbitrary that scale is.
LastYearsPumpkin@feddit.ch 1 year ago
It’s all arbitrary. Someone just decided to base a scale off of something and that something isn’t fixed from the start. The meter used to be based off the measurement of the earth, but now it’s based off of light.
It’s just some random semi-useful starting point that we all agree on so we’re using the same language.
MonkderZweite@feddit.ch 1 year ago
So, Kelvin in Physics, Celsius in daily usage and Fahrenheit…?
JoeKrogan@lemmy.world 1 year ago
Celcius is the logical choice. The others are just crazy.
nyoooom@lemmy.world 1 year ago
Kelvin and Celsius are the same, just offset onto absolute zero or the water freezing point
SexyPolariton@feddit.de 1 year ago
Yeah, often it is just way more convenient to use the Kelvin scale without any negative temperatures for some calculations and formulas then Celsius
butter@midwest.social 1 year ago
Because aligning to the temperature at which water boils is the objectively correct choice?
“Hey, how hot is it going to be today?”
“Well water is about 1/3rd the way to boiling, so about 30 degrees”
namingthingsiseasy@programming.dev 1 year ago
The fact that 99.5% of the global population uses it makes it the objectively correct choice.
The remaining .5% can keep bashing their heads against a wall if they like though
SuddenlyBlowGreen@lemmy.world 1 year ago
True, we should be using a temperature scale that was defined on how cold it was in Gdańsk, Poland in the winter of 1708, something the average man is more familiar with than water temperature, right?
Elivey@lemmy.world 1 year ago
We used water to decide a lot of measurements. 1ml of water is = 1 gram. A gram of water is also equal to 1 cm^3. It’s a beautiful system in that way. Water surrounds us and gives us life, it has chemically interesting properties that make this planet function. Why shouldn’t we just base everything off of this one substance?
shrugal@lemm.ee 1 year ago
When it’s “freezing cold” outside, what do you think is freezing? When something is “boiling hot”, what is boiling exactly?
We use water to describe temperature even without using Celsius, because it’s everywhere around us, and in three different physical states in our usual temperature range.
AI_toothbrush@lemmy.zip 1 year ago
Maybe ecause everyone uses it? Just so you know nobody even knows how fahrenhiet was defined first, everyone in the scientific community uses kelvin which is celsius but shifted so absolute zero is zero on it and the us actually uses si they just convert it to imperial so conversion between them is easier. There is point to imperial units other than its hard to switch between systems.
UraniumBlazer@lemm.ee 1 year ago
The temperature of water is very intuitive in nature. Dip ur hand in ice water. That’s almost 0C. Dip ur finger in boiling water (very quickly). That’s 100C. Dip ur finger in coffee whose temperature is fit for consumption: that’s around 75-80C. Ur hot water shower is likely between 37 and 41C…
Everything is tied quite well to water. Now compare that to F. What’s 0F? What’s 100F?
Forget the intuitiveness of celsius. It’s also much easier to calculate using celsius. When I say “My coffee was worth 80 calories”, I’m referring to a measure called “KCal”, which is the amount of energy required to raise the temperature of 1 litre, or 1 Kg of water by 1C. So if u ate something worth 100Kcal, you consumed enough energy to heat 1L/1Kg of water from 0C (ice) to 100C (steam). The average human requires around 2500 KCal everyday. Which is equivalent to 2.5 liters of water. Pretty cool, huh…
Just a quick sidenote: KCal is still not an “SI” unit. “Joules” are what we use here, but that’s another story.
Espi@lemmy.world 1 year ago
You can get used to any scale
Nima@lemmy.world 1 year ago
the Celsius nerds are mad at you, I guess. I love it when you see someone make a good point and the downvotes just pile on.
never change, reddit.
guriinii@lemmy.world 1 year ago
Since when is 0°C “fairly cold” it’s literally freezing.
morhp@lemmy.wtf 1 year ago
0°C is completely fine with jeans and a thick jacket, especially when it’s sunny and there isn’t much wind. It’s cold, but there’s probably not much ice or snow, if anything, probably mostly slush.
Compared to say -20 C where you should have a good ski jacket and ski pants, generally multiple layers everywhere, winter gloves and so on.
kamen@lemmy.world 1 year ago
It can be -20 C and you can be still fine with jeans and a jacket if it isn’t windy.
What I’m saying is temperature alone doesn’t tell you the whole story.
yetAnotherUser@feddit.de 1 year ago
But so is 100°F completely fine with a shirt and shorts and some shade.
So basically: |0°F| > |100°F|, where | is the mathematical absolute operator.
0°F is really cold, while 100°F is merely somewhat hot.
joeyb4589@sopuli.xyz 1 year ago
Humidity. I’m guessing you don’t live in a humid place because freezing temps are horrifically cold here. You will need a winter coat and multiple layers of your going to be outside for a while. I layer long Johns under my pants and wear my parka and a light jacket as well as 2 layers of socks. Everytime a northerner comes here they are shocked at the cold/heat. That’s because the air here is full of water to the point that you will actually get wet just from the humidity, not even sweating.
tryptaminev@feddit.de 1 year ago
It is also literally melting.
drcobaltjedi@programming.dev 1 year ago
I’ve been in -37C snow shoveling. Since then 0C doesn’t even register as cold to me
hemko@lemmy.dbzer0.com 1 year ago
Yep, and I’ve been in 110C in sauna. It’s pretty fucking hot but not death
kn33@lemmy.world 1 year ago
The northern half of the US laughs
ricecake@sh.itjust.works 1 year ago
The temperature that water freezes at is only fairly cold weather by a lot of people’s perception.
I’d call it “chilly”. No jacket for running to the mailbox, or if I’ll be outside for half an hour or so. Light jacket otherwise. I don’t expect it to snow, since it’s not actually cold enough usually, and there won’t be ice on the ground unless it’s just warmed up.So it might be “freezing”, but that doesn’t make it cold.
gazter@aussie.zone 1 year ago
It’s almost like being ‘fairly cold for humans’ is a wide range, and subjective, therefore useless as a baseline.
damo_omad@lemmy.world 1 year ago
In Aus we say it’s fucking freezing
Theharpyeagle@lemmy.world 1 year ago
Many places in the US, particularly in the Midwest, experience average temperatures at or below freezing (32°F) in the winter, so while it’s definitely cold, it’s often not considered really cold. It’s not until you move further towards 0 and the negatives that most people in that area feel really cold (like weather advisory levels). Of course the further north you go, the more normal those temps are.
joeyb4589@sopuli.xyz 1 year ago
Freezing temps here are definitely considered very cold. Cold enough that you need multiple layers and you should be wrapping your pipes to prevent freezing. It’s very humid here. Our freezing is insanely cold. Like chills you to your bones cold. Our hot here is insanely hot as well.
can@sh.itjust.works 1 year ago
We’re not made out of water.
CookieJarObserver@sh.itjust.works 1 year ago
Everything about -10 is warm.
who8mydamnoreos@lemmy.world 1 year ago
I would put it at a 3/10
EfreetSK@lemmy.world 1 year ago
I’d like to propose a discussion between a person from Arizona and a person from Alaska to define what is “Really hot outside”
Blamemeta@lemm.ee 1 year ago
Im from Texas, and 100F is “stay inside in the AC” weather. I bet an Arizonan would say the same.
Rozz@lemmy.sdf.org 1 year ago
Or cold
neonred@lemmy.world 1 year ago
WaxedWookie@lemmy.world 1 year ago
We should really normalise the Japanese system - it makes as much sense as the European system and has the benefit of being “alphabetically” sortable.
douglasg14b@lemmy.world 1 year ago
ISO-8601 or bust.
No other format really matters.
hemko@lemmy.dbzer0.com 1 year ago
0°C getting cold outside
100°C getting hot in saunachiliedogg@lemmy.world 1 year ago
Never any love for Rankine.
root_beer@midwest.social 1 year ago
Thank you, came to be a scold myself if you weren’t here for it
Mouette@jlai.lu 1 year ago
100° outside is dead
Kusimulkku@lemm.ee 1 year ago
True, you can be in 100’C indoors and be fine (sauna). Though I’ve heard some people think you’ll boil alive there lol
psycho_driver@lemmy.world 1 year ago
What did Kevin ever do to Fahrenheit or Celsius?
chaorace@lemmy.sdf.org 1 year ago
That’s lord Kevin to you, peasant
nucleative@lemmy.world 1 year ago
I like that
100c and 100K = dead but for different reasons
mathterdark@lemmy.world 1 year ago
Fahrenheit: how hot humans feel
Celsius: how hot water feels
Kelvin & Rankine: how hot atoms feel
ILikeBoobies@lemmy.ca 1 year ago
I don’t think how hot humans feel works at all, it’s just arbitrary
Can humans survive 100 degree heat? Yes so it doesn’t represent 100%
150 for 3rd degree burns (almost instant), does Fahrenheit go off base 150? Also no
What about cold? Well -40 requires a lot of layers, so then +40 should be pretty hot for humans right? Nope, because it’s not related to humans at all
ThatWeirdGuy1001@lemmy.world 1 year ago
100°F was supposed to be average human body temp. Guy who made the scale fucked up his math and we ended up actually at 98.6°F
Espi@lemmy.world 1 year ago
If farenheit represents how humans feel then 50 is the most comfortable temperature right?
s_s@lemmy.one 1 year ago
Fahrenheit was originally calculated to be 64 even divisions between water freezing temp and human body temp, then 32 more units below freezing.
Then ambient human body temp was recalculated from 96F to 98.6F.
So it’s based on powers of 2 of a bad measurement.
joeyb4589@sopuli.xyz 1 year ago
No one said it represents “100%”, whatever that is even supposed to mean. 100F is really hot outside. 0 F is really cold. Doesn’t have to make 100% sense. Celsius doesn’t make perfect sense either. There is no perfect magical scale that works completely.
KillAllPoorPeople@lemmy.world 1 year ago
I have no idea what this means.
Why do these matter? How often where humans live is it -40 degrees? Why does the scale need to be perfect in your opinion? And how is Celsius better?
Pulptastic@midwest.social 1 year ago
Neither will kill you (usually) but both suck.
yata@sh.itjust.works 1 year ago
Yeah, this gets repeated every time a discussion about temperature measuring systems comes up, but it is complete nonsense. The vast majority of Earth’s population are completely fine with measuring how hot they feel in celsius, it is only people who are unaccustomed to that system who thinks it is somehow unqualified to do that.
nucleative@lemmy.world 1 year ago
American who lives in a country that uses C now.
20=frickin cold 30=swampy ass 40=nope
Not enough degrees of separation
1847953620@lemmy.world 1 year ago
I lived for a third of my life in a country that uses Celsius, and the switch to Fahrenheit was not only seamless, it made much more sense to me intuitively. Whereas I was fine using Celsius, I don’t really want to go back.