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0 degrees celsius + 0 degrees celsius -

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Re: 0 degrees celsius + 0 degrees celsius -

#12

It looks like it must be using kelvin as its canonical units: 0C + 0C = 273.15 K + 273.15 K = 546.3 K = 273.15 C The weirdness is that conversions like that don't work for units that have different zero points. Perhaps addition of temperatures isn't really well defined? If 273.15 K + 273.15 K does not equal 0 C + 0 C, despite 273.15 K = 0 C, it's not clear what addition "means" in this context. One restricted form of…

Google can actually differentiate between the two meanings: degrees Celsius and Celsius degrees.

As you explained, the query posed by the title is meaningless, but 0 degrees Celsius + 0 Celsius degrees is handled correctly: http://www.google.com/search?&q=0+degrees+celsius+%2B+0+...

Re: 0 degrees celsius + 0 degrees celsius -

#14

Digging a little deeper... (0 degrees Celsius) + (0 degrees Celsius) - (0 degrees Celsius) = 0 degrees Celsius (0 degrees Celsius) - (0 degrees Celsius) = 0 kelvin (0 degrees Celsius) + (0 kelvin) = 0 degrees Celsius The last 2 of the 3 are wrong, so I'd say this is definitley a bug. EDIT: I think I figured it out. It's converting everything after the first temperature to Kelvin, without converting the first temp to…

0C - 0C => 0 - 273 = -273 = 0K (ok, weird this one then converts back to K)

Your math/logic is wrong, (A - A) => (B - A) you converted 0C to both 0 and 273.

Convert everything to Kelvin and it all makes sense. It's non-intuitive because 0C indicates a positive amount of energy rather than no energy as 0K does.

Re: 0 degrees celsius + 0 degrees celsius -

#15
post #9

It's meaningless to add temperatures when the zero level is at +273. It's like adding years relative to 2010 years ago - it would be meaningless to add this year - 2010 - with (say) 1666 - the year of the Great Fire of London. It's meaningful to take differences (the Great Fire happened 344 years ago), but not to add. (Unless we converted to some kind of absolute time units e.g. years since the big bang) I'd say what…

[deleted]

Re: 0 degrees celsius + 0 degrees celsius -

#16
The fact that people get out of secondary education with no real understanding of thermodynamics is a tragedy.

Case in point: There is currently no discussion in this thread of the difference between extensive and intensive properties of matter (highly relevant to the error Google makes here).

Re: 0 degrees celsius + 0 degrees celsius -

#19
post #12

It looks like it must be using kelvin as its canonical units: 0C + 0C = 273.15 K + 273.15 K = 546.3 K = 273.15 C The weirdness is that conversions like that don't work for units that have different zero points. Perhaps addition of temperatures isn't really well defined? If 273.15 K + 273.15 K does not equal 0 C + 0 C, despite 273.15 K = 0 C, it's not clear what addition "means" in this context. One restricted form of…

Google can actually differentiate between the two meanings: degrees Celsius and Celsius degrees . As you explained, the query posed by the title is meaningless, but 0 degrees Celsius + 0 Celsius degrees is handled correctly: http://www.google.com/search?&q=0+degrees+celsius+%2B+0+...

Ah, that's pretty interesting. It makes sense when you read the two phrasings next to each other, but it does seem like a pretty subtle wording difference. I think in practice people tend to differentiate which one is meant by context more than by "degrees Celsius" versus "Celsius degrees" being used consistently.

Should Google should convert the query somehow? It seems like adding two temperatures in degrees Celsius is something that never really makes sense (or subtracting, multiplying, or dividing them), so faithfully executing it like they currently do is rarely what's intended.

Re: 0 degrees celsius + 0 degrees celsius -

#20
post #14

Digging a little deeper... (0 degrees Celsius) + (0 degrees Celsius) - (0 degrees Celsius) = 0 degrees Celsius (0 degrees Celsius) - (0 degrees Celsius) = 0 kelvin (0 degrees Celsius) + (0 kelvin) = 0 degrees Celsius The last 2 of the 3 are wrong, so I'd say this is definitley a bug. EDIT: I think I figured it out. It's converting everything after the first temperature to Kelvin, without converting the first temp to…

0C - 0C => 0 - 273 = -273 = 0K (ok, weird this one then converts back to K) Your math/logic is wrong, (A - A) => (B - A) you converted 0C to both 0 and 273. Convert everything to Kelvin and it all makes sense. It's non-intuitive because 0C indicates a positive amount of energy rather than no energy as 0K does.

If you read my comment leading up to that, you'd see why I did it that way. But I agree with the other comment that it's more likely Google is just converting everything to Kelvin as it's canonical calculating form.
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