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The Mangler
2005-Oct-23, 12:44 AM
Ok, water freezes at 0deg.C, boils at 100deg.C, 0deg.K is absolute zero. My question is: How did we get degrees Farenheight? For instance, what is the significance of 0deg.F, if any?

The Supreme Canuck
2005-Oct-23, 01:08 AM
I've heard that 0 F was chosen as a temperature lower than it ever gets is Fahrenheit's country of origin because he disliked negative temperatures. No idea if it's true, though.

Added: And welcome to the forum!

Matthew
2005-Oct-23, 01:22 AM
Check out Wikipedia's article on the history of Fahrenheit (http://en.wikipedia.org/wiki/Fahrenheit#History).

The Mangler
2005-Oct-23, 01:40 AM
Interesting. It seems like there is no definate answer, I can understand why he didn't want to see negative numbers though, thats part of the reason I moved to Texas. I hate cold weather...

The Supreme Canuck
2005-Oct-23, 01:44 AM
I suppose it takes a certain kind of person to live up north. I actually like cold weather.

The Mangler
2005-Oct-23, 01:57 AM
I wish it was 70 (F) all the time. that would be perfect.

Gillianren
2005-Oct-23, 07:56 AM
I wish it was 70 (F) all the time. that would be perfect.

Too warm. 65. And a lot of plants and animals would like it colder.

The Supreme Canuck
2005-Oct-23, 08:30 PM
Between 50 and 60 F is about right for me.

zebo-the-fat
2005-Oct-23, 09:50 PM
0 F was the lowest temperature Mr Farenheit (spelling?) could get with an ice and salt mixture, 100 F was his body temperature. (What he didn't realise, is that the had a fever at the time!

(Who in the civilised world uses anything but Centigrade anyway?)

cyswxman
2005-Oct-23, 10:10 PM
Kelvins! Woohoo!

Shilappadikaram
2005-Oct-24, 12:47 AM
0 F was the lowest temperature Mr Farenheit (spelling?) could get with an ice and salt mixture, 100 F was his body temperature. (What he didn't realise, is that the had a fever at the time!

(Who in the civilised world uses anything but Centigrade anyway?)That's exactly right. There are though several other temperature scales in common usage, and some others that are only very rarely mentioned like the one that has water freezing at zero but boiling at 80. Offhand I've forgotten which one that was (Delisle maybe?) and feel too lazy to look it up again.

Kelvin is a better scale to use for math calculations than Celsius because it's starting point is absolute zero (about -273 degrees Celsius). Rankin is similar to Kelvin in that it's starting point is absolute zero (about -460 Fahrenheit), but it's calibrated in Fahrenheit degrees. The advantage of using absolute zero for your scales's starting point is that doubling the temperature number also doubles the heat content. That's not true with a scale like Celsius.

Other miscellaneous scales include Raumur, Newton, Delisle, Leyden, Dalton, Wedgewood, Hales, Ducrest, Edinburgh, and the Florentine. Some scales had odd histories, like the Celsius scale originally being called centigrade and running backwards. Some were in use for a century, but today you never hear of them.

Shilappadikaram
2005-Oct-24, 12:48 AM
0 F was the lowest temperature Mr Farenheit (spelling?) could get with an ice and salt mixture, 100 F was his body temperature. (What he didn't realise, is that the had a fever at the time!

(Who in the civilised world uses anything but Centigrade anyway?)That's exactly right. There are though several other temperature scales in common usage, and some others that are only very rarely mentioned like the one that has water freezing at zero but boiling at 80. Offhand I've forgotten which one that was (Delisle maybe?) and feel too lazy to look it up again.

Kelvin is a better scale to use for math calculations than Celsius because it's starting point is absolute zero (about -273 degrees Celsius). Rankin is similar to Kelvin in that it's starting point is absolute zero (about -460 Fahrenheit), but it's calibrated in Fahrenheit degrees. The advantage of using absolute zero for your scales's starting point is that doubling the temperature number also doubles the heat content. That's not true with a scale like Celsius.

Other miscellaneous scales include Réaumur, Newton, Delisle, Leyden, Dalton, Wedgewood, Hales, Ducrest, Edinburgh, and the Florentine. Some scales had odd histories, like the Celsius scale originally being called centigrade and running backwards. Some were in use for a century, but today you never hear of them.

novaderrik
2005-Oct-27, 10:21 AM
is it just a coincidence that farenheit and celsius are the same at -30?
i know they had to cross over somewhere, but -30 is a nice even number.

Maksutov
2005-Oct-27, 10:58 AM
is it just a coincidence that farenheit and celsius are the same at -30?
i know they had to cross over somewhere, but -30 is a nice even number.-40.

Maddad
2005-Oct-28, 03:33 AM
is it just a coincidence that farenheit and celsius are the same at -30? i know they had to cross over somewhere, but -30 is a nice even number.It's just a reflection of the math that they cross at the round number of -40. No coincidence at all.

novaderrik
2005-Oct-28, 10:19 AM
oops.. i KNEW it was -40, but for some reason, i typed -30.
must be the screwy new hours i'm working..

Joff
2005-Oct-31, 12:49 AM
Speaking of ice and salt...

I saw on TV somewhere that an ice/water/salt mixture in a coolbox is the fastest way to cool your beer down.

The Mangler
2005-Oct-31, 01:00 AM
Yeah, that was on MythBusters. Very good information to have.

Gillianren
2005-Oct-31, 05:20 AM
Speaking of ice and salt...

I saw on TV somewhere that an ice/water/salt mixture in a coolbox is the fastest way to cool your beer down.

Actually, if you saw the whole episode, a fire extinguisher was faster. However, the ice/water/salt blend was the most efficient--salt's a heck of a lot cheaper than a fire extinguisher.

The Mangler
2005-Nov-01, 12:23 AM
The fire extinguisher was the fastest, but the ice/water/salt was the coldest. I forget how cold it got after five minutes. Somewhere around 25deg.F I think.

jkmccrann
2005-Dec-20, 02:23 PM
This is probably going to sound stupid/weird, but I think the fact we don't have a unified temperature system and that different scales are used for different purposes, is something of a drawback for the planet as a whole, surely it'd be better if we had a scale we could all agree on?

In terms of finding a scale that would be new, but perhaps share some things in common with the 3 main scales of today, Fahrenheit, Celsius & Kelvin, and so have some sense of familiarity for people the world over, I thought of combining something from all 3.

In the New Scale (NS), in a nod to Kelvin, there would be no such thing as a negative temperature. Absolute Zero would be recognised as the New 0.

In a nod to Celsius, the freezing point of water would be a significant benchmark for the scale, such that 1000NS would be equal to 0 Celsius.

The nod to Fahrenheit is in more in spirit than in anything else, given the smaller `bandwidth' of each degree in the NS, quoting day-time temperatures one could simply quote the number of degrees above 1000NS of a temperature, instead of perhaps saying its going to be 1096 degrees NS today, one could simply say, its going to be 96NS today, kinda a slang way to approach the whole thing from a weather-forecaster point of view.

More than anything when I worked this out it was an exercise in theory to see how current temperatures would translate onto the new scale, and for that matter the 1000NS can be set at 0 deg. F as well, doesn't really matter. The fact is, our temperature scale should start at 0, makes explaining things a whole lot easier in the long term, and since we've now discovered what Absolute Zero actually is, maybe we could reform the System in some way.

Having 273.16 as the freezing point of water is simply no good for the layman because its simply too obscure a number to ever really catch on.

I guess for the purposes of this scale, perhaps 500NS could be the freezing point of water, or 400NS? Doesn't really matter, but it should be a readily rememberable number for the general public.

Anyway, that's just my crazy idea for the day. And yes, choosing the freezing point of water as an important marker is completely arbitrary, but it is a temperature that is universally recognised and therefore a good reference point for any scale for the layman out there.

hhEb09'1
2005-Dec-20, 07:55 PM
In a nod to Celsius, the freezing point of water would be a significant benchmark for the scale, such that 1000NS would be equal to 0 Celsius.I like it. Can we name it the Baut Scale? "1096 Baut" would be 1096B, or 96b.

Let's see, that's 96*273.16/1000, or 26.22 C, 79.2 F, right?

X-COM
2005-Dec-20, 08:12 PM
I prefer the Kelvin/Celcius combo and they go nicely hand in hand. Just add 273 to Celsius to get a result in Kelvin and subtract 273 to get back to Celcius. Really high temperatures (like he surface temperature of the sun) are for all practical resons the same.

For more accurancy use 273.15 but the general idea should be understood. They both use the same scale.

Swift
2005-Dec-20, 09:57 PM
I like it. Can we name it the Baut Scale? "1096 Baut" would be 1096B, or 96b.

Let's see, that's 96*273.16/1000, or 26.22 C, 79.2 F, right?
So if someone asked you what the temperature was, you could say it was a "baut" one thousand. :p

Maddad
2005-Dec-20, 11:04 PM
Somebody outta give that man a Swift kick for a comment like that.

jkmccrann
2005-Dec-22, 06:01 AM
I like it. Can we name it the Baut Scale? "1096 Baut" would be 1096B, or 96b.

Let's see, that's 96*273.16/1000, or 26.22 C, 79.2 F, right?

Baut Scale sounds good to me. I like the suggested capitals and lower-case differentiation as well.

I guess one thing the scale does do is give the colder states a chance to experience some `higher' numbers during Winter.

If you want to write up a small report on it with comparative scales and post it somewhere on the Web, we can have joint ownership of it!

Then all we need to do is get some PR whizkids involved and sell it to everyone. `New Temperature Scale for the New Century!' Yada yada yada. I can see it now, interviews on the Today show, 60 Mins etc. etc. etc. lol!

Of course, I will get around to writing it up someday, but the offer is definitely there at the moment.....

Lord Jubjub
2005-Dec-22, 11:42 PM
is it just a coincidence that farenheit and celsius are the same at -30?
i know they had to cross over somewhere, but -30 is a nice even number.

F=9C/5+32

F=C

thus:
F=C=-40

mickal555
2005-Dec-30, 04:34 PM
The fire extinguisher was the fastest, but the ice/water/salt was the coldest. I forget how cold it got after five minutes. Somewhere around 25deg.F I think.

Dry ice had it freezing....


and Farenhight is evil...

pumpkinpie
2005-Dec-30, 04:46 PM
(Who in the civilised world uses anything but Centigrade anyway?)

Me!!

zebo-the-fat
2005-Dec-30, 05:19 PM
Me!!

:confused:

Cosmo
2008-Aug-13, 03:03 PM
Wake up, thread! I don't see any recent posts to this thread and I also don't see any discussion of this question I thought of recently: Body temperature is an even 37 degrees C but an uneven 98.6 degrees F. I read the discussion here (?) and elsewhere about the history of 98.6 and an adjustment made from the original 100. Is it total conincidence that 98.6 F translates into 37-point-nothing or is it part of the larger Celsius schem? Thanks, group!

Delvo
2008-Aug-13, 04:19 PM
It was measured at 37 with only two digits of precision, so no 36.7 or 37.216. Using the simple conversion formula to Fahrenheit (divide by five, multiply by nine, add thirty-two), yields 98.6, but the extra digit implies a greater level of precision than the original number "37" contained. Human body temperature is not actually as narrowly contrained as that decimal implies it to be; if your normal healthy temperature were off of it by a couple of degrees, it wouldn't even make you the least bit unusual. If the original measurements that gave us the loose estimate "37" had been done in Fahrenheit in the first place, they would have just called it "99" or even given a range like "97-100". And then it would be the Celsius scale that got the weird number from conversion, such as "37.22222222222222222...".

John Jones
2008-Aug-13, 05:33 PM
The story my chemistry professor gave is that Fahrenheit set the temperature of melting seawater as zero, and his wife's body temperature when she had a fever as 100.

I have no supporting evidence.

Cosmo
2008-Aug-13, 05:36 PM
Thanks, Delvo! I KNEW someone here would know the answer.

And thanks also John Jones. I saw the body-temperature-with-a-fever story somewhere too, maybe Wikipedia, but it was Mr. F. not Mrs. F. in that version.

John Jones
2008-Aug-13, 05:38 PM
From wikipedia:


According to Fahrenheit himself in an article he wrote in 1724,[1] he determined his scale by reference to three fixed points of temperature. The zero point is determined by placing the thermometer in a mixture of ice, water, and ammonium chloride, a salt. This is a type of frigorific mixture. The mixture automatically stabilizes its temperature at 0 F. He then put an alcohol or mercury thermometer into the mixture and let the liquid in the thermometer descend to its lowest point. The second point is the 32nd degree found by putting the thermometer in still water as ice is just forming on the surface.[2] His third point, the 96th degree, was the level of the liquid in the thermometer when held in the mouth or under the armpit. Fahrenheit noted that, using this scale, mercury boils at around 600 degrees. Later work by other scientists observed that water boils about 180 degrees higher than the freezing point and decided to redefine the degree slightly to make it exactly 180[1] It is for this reason that normal body temperature is 98.6 on the revised scale (whereas it was 96 on Fahrenheit's original scale).[3]

According to a letter Fahrenheit wrote to his friend Herman Boerhaave,[4] his scale built on the work of Ole Rmer, whom he had met earlier. In Rmer’s scale, the two fixed reference points are that brine also freezes at 0 degrees and water boils at 60 degrees. He observed that, on this scale, water freezes at 7.5 degrees. Fahrenheit multiplied each value by four in order to eliminate the fractions and increase the granularity of the scale (resulting in 30 and 240 degrees). He then re-calibrated his scale between the freezing point of water and normal human body temperature (which he observed to be 96 degrees); he adjusted the scale so that the melting point of ice would be 32 degrees, so that 64 intervals would separate the two, allowing him to mark degree lines on his instruments by simply bisecting the interval six times (since 64 is 2 to the sixth power).[5]

Swift
2008-Aug-13, 05:46 PM
The story my chemistry professor gave is that Fahrenheit set the temperature of melting seawater as zero, and his wife's body temperature when she had a fever as 100.

I have no supporting evidence.
I've heard a similar story, except 100F was Fahrenheit's normal body temperature, and he just ran a little hotter than average.

ryanmercer
2008-Aug-14, 01:07 AM
Too warm. 65. And a lot of plants and animals would like it colder.

I could go for 65 :)

Jens
2008-Aug-14, 02:12 AM
This is probably going to sound stupid/weird, but I think the fact we don't have a unified temperature system and that different scales are used for different purposes, is something of a drawback for the planet as a whole, surely it'd be better if we had a scale we could all agree on?


Actually, we do, with the exception of a couple of countries. Kelvin is just Celsius adjusted for scientific purposes, really.

dgavin
2008-Aug-14, 03:45 AM
Personally, I like the granulaity of F over C. Measurments in the metric system was easy enough to adapt to for me except for the temperature scale.

I gave up on Centigrade when Air temps i could feel were diferent, barely changed in that scale.

I'd rather see a new Temp scale (I'll call it HN for now) of 0 for freezing, 200 for boiling, for weather related reporting, and then Kelvin for all other things.

Basiaclly equates to 99.98 K per 200 HN

Conversion from Kelvin to HN is a simple (K*2.0004) -546.409276, Other direction would be (HN + 546.409276) / 2.0004. Room temperatures would be around 40 on this scale.

*edit to add*

The beauty of this one is that for common people, adjusting to it is a simple shift in thinking. For people used to F, just subtract 32, for people used to C, just double.

Ivan Viehoff
2008-Aug-14, 09:59 AM
I remember being taught that Fahrenheit set 100F as the body temperature of a horse, though this doesn't seem borne out in the references.

Bearded One
2008-Aug-16, 12:19 AM
(Who in the civilised world uses anything but Centigrade anyway?)I prefer Fahrenheit because 1 degree Centigrade is to big of a temperature change for comfort control. A thermostat that doesn't support a decimal point does not offer fine enough control when set to the Centigrade scale.

Trebuchet
2008-Aug-16, 04:05 AM
Personally, I like the granulaity of F over C. Measurments in the metric system was easy enough to adapt to for me except for the temperature scale.

I gave up on Centigrade when Air temps i could feel were diferent, barely changed in that scale.

I'd rather see a new Temp scale (I'll call it HN for now) of 0 for freezing, 200 for boiling, for weather related reporting, and then Kelvin for all other things.

Basiaclly equates to 99.98 K per 200 HN

Conversion from Kelvin to HN is a simple (K*2.0004) -546.409276, Other direction would be (HN + 546.409276) / 2.0004. Room temperatures would be around 40 on this scale.

*edit to add*

The beauty of this one is that for common people, adjusting to it is a simple shift in thinking. For people used to F, just subtract 32, for people used to C, just double.

I like it! I've always preferred Fahrenheit for discussing ambient temperatures because the Celsius scale seemed too coarse. And 0 to 100 Fahrenheit approximates, reasonably well, the atmospheric temperature range in temperate parts of the globe. Your scale doesn't do that quite as well, but it would be usable.

nauthiz
2008-Aug-16, 02:51 PM
I've always preferred Farenheit because that's what I was raised with. :p

dgavin
2008-Aug-16, 04:52 PM
I like it! I've always preferred Fahrenheit for discussing ambient temperatures because the Celsius scale seemed too coarse. And 0 to 100 Fahrenheit approximates, reasonably well, the atmospheric temperature range in temperate parts of the globe. Your scale doesn't do that quite as well, but it would be usable.

So if people like it, how would one go about getting it out there?

Post it on Wiki and see what happens? What to call it though. HN Scale for Human Normalized Temperature, or should I suck up to Phil and Fraiser and call it B for Baut Temperature?

hhEb09'1
2008-Aug-16, 11:25 PM
Conversion from Kelvin to HN is a simple (K*2.0004) -546.409276, Other direction would be (HN + 546.409276) / 2.0004. Room temperatures would be around 40 on this scale.It's closer to 2.00032, idnit?

Why not just use 2?
The beauty of this one is that for common people, adjusting to it is a simple shift in thinking. For people used to F, just subtract 32, for people used to C, just double.Common people? You mean, inaccurate people? :)

Hornblower
2008-Aug-16, 11:51 PM
Personally, I like the granulaity of F over C. Measurments in the metric system was easy enough to adapt to for me except for the temperature scale.

I gave up on Centigrade when Air temps i could feel were diferent, barely changed in that scale.

I'd rather see a new Temp scale (I'll call it HN for now) of 0 for freezing, 200 for boiling, for weather related reporting, and then Kelvin for all other things.

Basiaclly equates to 99.98 K per 200 HN

Conversion from Kelvin to HN is a simple (K*2.0004) -546.409276, Other direction would be (HN + 546.409276) / 2.0004. Room temperatures would be around 40 on this scale.

*edit to add*

The beauty of this one is that for common people, adjusting to it is a simple shift in thinking. For people used to F, just subtract 32, for people used to C, just double.
Does not compute, big time. Subtracting 32 from Fahrenheit gives boiling point of 180, not 200. Please explain.

What's with that coefficient of 2.0004? If HN melting and boiling points are 200 apart, why is the conversion factor not exactly 2?

hhEb09'1
2008-Aug-17, 01:36 PM
What's with that coefficient of 2.0004? If HN melting and boiling points are 200 apart, why is the conversion factor not exactly 2?Because the boiling point and melting point are not exactly 100 apart in Kelvin :)

HenrikOlsen
2008-Aug-17, 03:21 PM
<whailing>but everyone knows 9/5 is exactly 2</whailing>

hhEb09'1
2008-Aug-17, 11:57 PM
Is that a portmanteau of wail and whine? :)

HenrikOlsen
2008-Aug-18, 10:00 AM
Yes

JonClarke
2008-Aug-18, 11:59 AM
I have used celcius for 40 years now, much more useful than the other one.

Gigabyte
2008-Aug-18, 02:30 PM
According to Fahrenheit himself in an article he wrote in 1724,[1] he determined his scale by reference to three fixed points of temperature. The zero point is determined by placing the thermometer in a mixture of ice, water, and ammonium chloride, a salt. This is a type of frigorific mixture. The mixture automatically stabilizes its temperature at 0 F. He then put an alcohol or mercury thermometer into the mixture and let the liquid in the thermometer descend to its lowest point. The second point is the 32nd degree found by putting the thermometer in still water as ice is just forming on the surface.[2] His third point, the 96th degree, was the level of the liquid in the thermometer when held in the mouth or under the armpit. Fahrenheit noted that, using this scale, mercury boils at around 600 degrees. Later work by other scientists observed that water boils about 180 degrees higher than the freezing point and decided to redefine the degree slightly to make it exactly 180 degrees higher[1]. It is for this reason that normal body temperature is 98.6 on the revised scale (whereas it was 96 on Fahrenheit's original scale).[3]

http://en.wikipedia.org/wiki/Fahrenheit#History

HenrikOlsen
2008-Aug-18, 02:55 PM
That link was given in post #2 of the thread:)

mahesh
2008-Aug-18, 02:55 PM
Speaking of ice and salt...
I saw on TV somewhere that an ice/water/salt mixture in a coolbox is the fastest way to cool your beer down.

This was 'before tv was invented'.

I remember that wooden bucket....making ice-cream at home....after supper...we put in some water / crushed ice...quite a bit../ salt.
position the container of goodies / assemble the top, churning mechanism.
click lock / some elbow grease ...twenty mins/half an hour later we had sore arms and yummy icecream. freshly made. great fun.


-40.

nice to see Mak, The Quality Control! :D

mahesh
2008-Aug-18, 03:54 PM
I have used celcius for 40 years now, much more useful than the other one.
celsius

yes and i call it 'centigrade' too!

body temperature in Fahrenheit makes sense to me...
bells ring either side of 96/100 range.

Jay200MPH
2008-Aug-18, 06:10 PM
I grew up in Canada in the '80s so I'm "fluent" in both systems. However for some reason my family always measured water temperature (swimming pool, bath, cooking, etc.) in F and air temperature in C. I have literally no conception of how either scale applies to the "wrong" medium. If you tell me that the pool water is 30C that number is meaningless.

I blame my parents.

- J

JonClarke
2008-Aug-18, 10:17 PM
celsius

yes and i call it 'centigrade' too!

body temperature in Fahrenheit makes sense to me...
bells ring either side of 96/100 range.

Bells ring either side of 38 degrees C.

It is amazing the excuses people come up with to avoid using the standard system.

Jon

Van Rijn
2008-Aug-18, 10:47 PM
It is amazing the excuses people come up with to avoid using the standard system.

Jon

The "standard system" depends on where you live, and on what work you do.

GeorgeLeRoyTirebiter
2008-Aug-18, 10:54 PM
It is amazing the excuses people come up with to avoid using the standard system.

I'm all for sticking with imperial measurements for no other reason than it annoys some people.

mahesh
2008-Aug-18, 11:13 PM
Bells ring either side of 38 degrees C.

It is amazing the excuses people come up with to avoid using the standard system.

Jon
yah! :D

as a child...children's fever was measured by a Fahrenheit thermometer...in the mouth / under the armpit job...so i am inclined towards that sense

other associations have been through the Celsius scale, so i am aware more in that scale...

but rationally thinking, it doesn't really matter whichever scale applies, easy to convert into either.

i wasn't aware a standard system exists...i would have thought we are exposed to both these scales, commonly!

best regards

cjl
2008-Aug-19, 06:19 AM
Bells ring either side of 38 degrees C.

It is amazing the excuses people come up with to avoid using the standard system.

Jon
The Celsius scale is about the only part of the metric system that I don't fully support. I prefer the finer gradients of the Fahrenheit scale, and both are based on somewhat arbitrary ideas.

Jens
2008-Aug-19, 12:12 PM
I'm all for sticking with imperial measurements for no other reason than it annoys some people.

Then you are in favor of breaking wind in elevators? :)

Gigabyte
2008-Aug-19, 12:28 PM
Post #2 ->
I've heard that 0 F was chosen as a temperature lower than it ever gets is Fahrenheit's country of origin because he disliked negative temperatures. No idea if it's true, though.

Added: And welcome to the forum!

Pst #4->
Interesting. It seems like there is no definate answer, I can understand why he didn't want to see negative numbers though, thats part of the reason I moved to Texas. I hate cold weather...

Hmm....