# Very Hard Question

#### MRCHEM

1 Celsius= 274.15kelvin Right

So 274.15+274.15=548.30 Kelvin(2 Celsius)

But
2 Celsius Is= 273.15 Im Confused Help

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#### Line

Actually 2 Celsius should be 275 Kelvin.

The answer is very easy. Celsius's origin is at the freeizing point of water, that's 0. Anything below 0(freezing) is negative, anything above is positive. Same for Farenheut accept freezing for water is 32.

Kelvin is different, it works at the absoloute coldest temperature possible with no heat. That's called Absolute Zero. That's about -273 Celsius . Therefore the freezing point of water on Kelvin is 273. 1 Celsius=274 and
2=275.

#### Hawknc

In addition to what Line said, the trick lies in the magnitudes of one degree Celcius and one Kelvin, which happen to be the same. The zero point is simply much lower for Kelvin (-273 deg C). So to convert any Celcius measurement to Kelvin, all you have to do is add 273 and voila, you have your answer.

#### MRCHEM

Im Still Confused Because The Ratio Isnt Right, How Come

#### mengshuen

they are not related by a ratio, they are related by a difference of 273.

so 2 celsius is 273+2=275
0 celsius = 273+0=273
-273 celsius = 273-273=0

#### Hawknc

If you increase the temperature of an object by 1 deg C, it's EXACTLY the same as increasing it by 1 K. So, if you really want ratios, the ratio magnitudes of Celcius to Kelvin is 1:1.

#### Saketh

Hawknc said:
If you increase the temperature of an object by 1 deg C, it's EXACTLY the same as increasing it by 1 K.
Correct.
So, if you really want ratios, the ratio magnitudes of Celcius to Kelvin is 1:1.
Not really - the ratio changes. mengshuen was correct in saying that they are not related by a ratio, but by a difference. I understand what you're saying, but thinking of this in terms of ratios is unnecessary confusion.

What you're saying would be correct if you changed it to: the ratio of the magnitudes of degrees Celsius + 273 and of degrees Kelvin is 1:1.

#### Astronuc

Staff Emeritus
MRCHEM said:
Im Still Confused Because The Ratio Isnt Right, How Come
It would appear that you are thinking of a function, y = m x in which K is proportional to °C, where m is a proportionality constant. This is not the case.

Temp (K) = Temp (°C) + 273.15,
so 0 K = -273.15 K, or 273.15 K = 0°C, or 100°C = 373.15 K.

this is like y = ax + b, where a = 1, or y = x + b.

the temperature 'difference' in K = temperature difference in °C.

See - http://hyperphysics.phy-astr.gsu.edu/Hbase/thermo/temper.html#c3

#### Hawknc

Lol, that sentence was supposed to be "the ratio OF magnitudes of Celcius to Kelvin is 1:1". That's what I get for typing so late at night.

#### MRCHEM

So You Cant Really Add Kelvins And Then Express Them In Celsius? Because Ive Done That In Our Test Cause I Relly Dont Know The Equation What I Know Is That 1 Deg C Is=274.15 Kelvin

#### fargoth

uhm, you can... everyone here explained it already...

if you take measure 273.15 Kelvin, it means you measured 0 Celsius.
if you add 25 Kelvins to that temperature you get 298.15 Kelvin = 25 Celsius!

-273.15 Celsius = 0 Kelvin
-272.15 Celsius = 1 Kelvin
-271.15 Celsius = 2 Kelvin
...
-1 Celsius = 272.15 Kelvin
0 Celsius = 273.15 Kelvin
1 Celsius = 274.15 Kelvin
2 Celsius = 275.15 Kelvin
...

so, as astronuc said:
<Kelvin> = <Celsius> + 273.15
and
<T1 in Kelvin> - <T2 in Kelvin> = <T1 in celsius> - <T2 in celsius>

#### MRCHEM

Take This As An Example You Have 274.15 Kelvin Which Is 1 Celsius
So If You Add Another 274.15 Kelvin Which Is 1 Celsius To Another 274.15=1 Celsius Then You Will Have 2 Celsius Right Or Not Because 2 Celsius=275.15 Kelvin

#### fargoth

<T1>+<T2-T1>=<T2>

and <T2-T1> is the same for Celsius and for Kelvins.

if you add 50 Kelvins to 273.15 Kelvin you get 323.15 Kelvin, which is equal to 50 Celsius.

#### Integral

Staff Emeritus
Gold Member
MRCHEM said:
Take This As An Example You Have 274.15 Kelvin Which Is 1 Celsius
So If You Add Another 274.15 Kelvin Which Is 1 Celsius To Another 274.15=1 Celsius Then You Will Have 2 Celsius Right Or Not Because 2 Celsius=275.15 Kelvin

You fail to differentiate between specific temperatures and the magnitude of a change of temperature. There is actually notation which specifies this. We have:

10C = 274.150K

but at the same time we have:

1C0 = 1K0

Notice the difference in location of the degree symbol. When it is to the right of the number it refers to a specific point on the scale, when it is to the right of the letter (C, k or F) it means a CHANGE on that scale.

Give it some thought.

#### MRCHEM

ahhhhhhhhh thanks

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