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19/05/2013 00:32:19

Author Topic: Can we get "twice as cold" as 0 degrees C?  (Read 2789 times)

pippystardust

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  • on: 27/03/2012 20:41:18
if it is 0 degrees celcius outside and the weatherman says that it will be twice as cold tomorrow ...what will the temperature be tomorrow ?
« Last Edit: 29/03/2012 18:47:00 by chris »

pippystardust

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  • Reply #1 on: 27/03/2012 20:48:16
If the temperature is zero degrees C  and the weatherman says it will be twice as cold tomorrow ...what will the temperature be tomorrow ?

Bored chemist

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  • Reply #2 on: 27/03/2012 21:13:51
It will  be cold enough that you need a better weatherman.

CliffordK

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  • Reply #3 on: 27/03/2012 21:16:51
-137° C

pippystardust

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  • Reply #4 on: 27/03/2012 23:21:15
11 views   no suggestions yet !

CliffordK

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  • Reply #5 on: 28/03/2012 01:18:24
You have started two topics.
It is generally frowned upon to start two identical threads.

(Now merged).
« Last Edit: 28/03/2012 21:44:01 by CliffordK »

Nizzle

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  • Reply #6 on: 28/03/2012 10:20:39
If the temperature is zero degrees C  and the weatherman says it will be twice as cold tomorrow ...what will the temperature be tomorrow ?

Well, that weatherman can't be correct because 0 degrees C = 273.15 K, and twice as cold will then be 136.575 K, or -136.575 degrees C. I think the whole world would come to a stop if it were to become that cold...

Sprool

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  • Reply #7 on: 28/03/2012 13:40:15
Stands to reason it will be 16F.
Probably.

Geezer

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  • Reply #8 on: 28/03/2012 14:30:59
Obviously, it will be 245.8 degrees.

CliffordK

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  • Reply #9 on: 28/03/2012 21:25:40
If 70°F (21°C) is considered "comfortable".

So...  0°C would be 21 degrees Cold.

So, twice as cold would have to be -21°C, or -6°F


pippystardust

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  • Reply #10 on: 29/03/2012 18:37:05
why are some people being so literal ? the weatherman didn't REALLY say that...its a hypothetical question ! 

chris

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  • Reply #11 on: 29/03/2012 18:46:44
What about windchill?

Geezer

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  • Reply #12 on: 29/03/2012 20:16:25
What about windchill?

Windchill is an attempt by weathermen to "dumb-down" science so they can make meaningless statements like "twice as cold"   ;D
 
It's pretty qualitative.

pippystardust

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  • Reply #13 on: 30/03/2012 08:33:15
even though this is a bit of fun    why are people just coming up with  figures and no explanation of how they came up with it ?  Int that a teensy bit pompous to assume that everyone will accept that they are correct?
 Its not a very scientific way of presenting something either is it?  if you presented an essay like that without backing up claims then you would either fail or get the essay returned unmarked

CliffordK

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  • Reply #14 on: 30/03/2012 23:37:37
even though this is a bit of fun    why are people just coming up with  figures and no explanation of how they came up with it ?  Int that a teensy bit pompous to assume that everyone will accept that they are correct?

I think that is part of the fun...  and allows one to puzzle over the answer.

"Twice as hot" is a pretty simple concept, take the temperature on your favorite temperature scale, Kelvin, Celsius, or Fahrenheit, and double it, although scientifically speaking, one should use Kelvin for such a comparison.

"Twice as cold" is much more ambiguous because if you double a temperature, you get something hotter.

Obviously

2 x 0°C = 0°C.
˝ x 0°C = 0°C.

-137° C
Well, that weatherman can't be correct because 0 degrees C = 273.15 K, and twice as cold will then be 136.575 K, or -136.575 degrees C. I think the whole world would come to a stop if it were to become that cold...

Both these are the same, using half the temperature in Kelvin, rather than "twice as cold".

Stands to reason it will be 16F.
Probably.

0°C = 32°F.  So, half that temperature in Fahrenheit is 16°F, or -8.89°C

Keep in mind that Fahrenheit is widely used in the USA for ambient temperatures.

Obviously, it will be 245.8 degrees.

Hmmm... :o ?

Ok, on the Rankine Scale, 0°C = 491.67 °R.
Half of 491.67 °R = 245.8°R
xx(
If 70°F (21°C) is considered "comfortable".
So...  0°C would be 21 degrees Cold.
So, twice as cold would have to be -21°C, or -6°F

Here I tried to redefine what "cold" means.  In this case, anything below your "optimum" temperature is considered "cold", and anything above it is "hot".  So, once one gets a "cold scale", it is easy enough to double it.

In a Geezeresque fashion, let me try another answer using the Delisle Scale..  This scale has the advantage over the other scales in that the larger the number, the colder the temperature.

So,

0°C = 150°De.

One can then easily calculate that twice as cold would simply be 150°De x 2 = 300°De, or −100.00°C, or −148.00°F.

See what you get for asking such a question in a "Science Forum"  :o)

Geezer

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  • Reply #15 on: 31/03/2012 01:30:32
Good spot on the Rankine!

pippystardust

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  • Reply #16 on: 02/04/2012 23:26:01
Good spot on the Rankine!

0 degrees is O degrees in ANY scale   so what is twice as cold as 0 degrees?  its not about what you consider "cold"  its what 0 degrees is !
I will reword my question in a boring way       
"What is twice as cold as 0 degrees?"     (in ANY scale)

PS   just so thst you know that I am actually thinking scientifically...I assume that the upper most temp on the scale makes a difference to the answer !

yor_on

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  • Reply #17 on: 07/04/2012 14:44:46
It's an expression i guess?
And a good thing to philosophize over, over a beer :)

I don't know, what is 'zero'?

Nizzle

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  • Reply #18 on: 10/04/2012 09:27:00
"What is twice as cold as 0 degrees?"     (in ANY scale)

-0 degrees :p

 

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