The Naked Scientists

The Naked Scientists Forum

Author Topic: Why are there two scales of temperature ?  (Read 2723 times)

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Why are there two scales of temperature ?
« on: 26/07/2007 14:55:12 »
Dear Peeps of Centigradal farenheital luff and joy,

See this thermometer:



nice isn't it ?....notice how centri-farenheital it is ?

Am just curious as to why there are TWO scales of temperature on my thermometer ? (Celsius and Fahrenheit..they're the main two eh ?)

which came first and why did we just not stick with it ?

I have to say I'm a Celsius man myself !


 

Offline dentstudent

  • Neilep Level Member
  • ******
  • Posts: 3146
  • FOGger to the unsuspecting
    • View Profile
Why are there two scales of temperature ?
« Reply #1 on: 26/07/2007 15:05:00 »
(There's also Kelvin)
 

another_someone

  • Guest
Why are there two scales of temperature ?
« Reply #2 on: 26/07/2007 15:09:25 »
There are at least 5 scales of temperature, if one includes Kelvin, Rankine, and RÝmer (there may be others I am not aware of).

Its the old adage about standards being a good thing, which is why there are so many of them (mostly incompatible with each other).
 

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Why are there two scales of temperature ?
« Reply #3 on: 26/07/2007 15:10:54 »
(There's also Kelvin)

True true...but I don;t recall the need to measure absolute zero in my home !  ;D
 

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Why are there two scales of temperature ?
« Reply #4 on: 26/07/2007 15:13:00 »
There are at least 5 scales of temperature, if one includes Kelvin, Rankine, and RÝmer (there may be others I am not aware of).

Its the old adage about standards being a good thing, which is why there are so many of them (mostly incompatible with each other).

Gosh !!..are all these scales of temperature there to accommodate the extreme temperatures that would look silly when represented by another...?
 

another_someone

  • Guest
Why are there two scales of temperature ?
« Reply #5 on: 26/07/2007 15:21:09 »
There are at least 5 scales of temperature, if one includes Kelvin, Rankine, and RÝmer (there may be others I am not aware of).

Its the old adage about standards being a good thing, which is why there are so many of them (mostly incompatible with each other).

Gosh !!..are all these scales of temperature there to accommodate the extreme temperatures that would look silly when represented by another...?

There are lots of reasons why one person or group preferred one measure to another.  At least in the case of Fahrenheit, Kelvin, and Rankine, the desire to avoid negative temperatures seems to have been part of the reason (both Kelvin and Rankine are based on absolute zero, and so avoid negative temperatures in that way, but are based on the more historic Centigrade (now renamed Celsius) and Fahrenheit scales; while the Fahrenheit scale is said, at least by some (I have heard other explanations, and I am not sure there is a definitive answer), to have been based on the coldest winter temperature that its originator had measured, and so avoiding having to use negative temperatures for measuring in the world he knew).
 

Offline dentstudent

  • Neilep Level Member
  • ******
  • Posts: 3146
  • FOGger to the unsuspecting
    • View Profile
Why are there two scales of temperature ?
« Reply #6 on: 26/07/2007 15:26:33 »
(An aside) For a quick and dirty method of going from °C to °F, double and add 30. The real method is multiply °C by 1.8 and add 32. For 10°C, the methods give the same. Also, -40°C = -40°F.
 

Offline kdlynn

  • Neilep Level Member
  • ******
  • Posts: 2851
    • View Profile
Why are there two scales of temperature ?
« Reply #7 on: 26/07/2007 15:52:03 »
i knew i was doing something wrong when i was trying to convert that! i forgot the multiplying part and was just adding thirty two. lol.
 

lyner

  • Guest
Why are there two scales of temperature ?
« Reply #8 on: 27/07/2007 23:51:24 »
Quote
Quote from: dentstudent on 26/07/2007 16:05:00
(There's also Kelvin)

True true...but I don;t recall the need to measure absolute zero in my home !  grin
But absolute zero is very relevant to you, even in or around the home - the rate at which a gas expands is proportional to its 'absolute' temperature - in Kelvin. If you double the (Celcius) temperature of a balloon from 20C to 40C, its volume (or pressure) doesn't double, it just increases by  a factor of 313/293 - the fractional increase in Kelvin. Motor tyres would burst if it wasn't that way.
 

The Naked Scientists Forum

Why are there two scales of temperature ?
« Reply #8 on: 27/07/2007 23:51:24 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums