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You haven't corrected the posters mistake, you've repeated it.

Intervals can only be converted into percentages across another interval, you've decided that the whole interval is the interesting part but it isn't, 0K is as abitrary as 0C for this purpose. Is a day 1/7th of a week or 1/365th of a year? Yes. It's also some tiny fraction of all time since the Big Bang, but who cares about that? That's your absolute interval.

There isn't a proper way to do it and it's nearly always a mistake to try.



I disagree.

Their way of doing the conversion is far more principled than the original commenter's.

It's absolutely appropriate to do a percentage conversion based in Kelvin, the percentage has a fundamental meaning in terms of the actual increase in kinetic energy. You would get the same percentage if you did the calculation in Rankine because they're both 0-based temperature scales.


No, 0 K isn't arbitrary. That's exactly the point; it's the lowest temperature for which the definition of temperature makes sense.

Your analogy about days relating to weeks or years is wrong. This is a matter of scaling. In this sense, Kelvin is of course arbitrary, but said scaling does not matter for the computations in question.

If the poster had written "49 C is 6% further than 46 C from the point at which water freezes", then we'd be in agreement that their choice of interval is no worse or better than others. But absent such a clear labelling, the only notion that makes sense is the absolute one.


No. You are comprehensively wrong about the relationship between intervals and other intervals with regard to percentages, and you have refused to learn from what I just said.

> Kelvin is of course arbitrary

Listen to yourself if you won't listen to me.

Edit: read up on the difference between temperature and heat. I suspect that your mental model of that relationship is wrong, and that's why you're making this mistake.


> > Kelvin is of course arbitrary

> Listen to yourself if you won't listen to me.

Like I said: Kelvin is arbitrarily scaled. Scaling doesn't matter when it comes to ratios. Celsius on the other hand is also arbitrarily offset. That matters.

> Edit: read up on the difference between temperature and heat. I suspect that your mental model of that relationship is wrong, and that's why you're making this mistake.

I'm quite aware, thank you very much. This whole subthread is about temperature. To be clear: I'm not criticising OP's writings about energy requirements. I'm merely talking about:

> Sure that's only a 6.5% increase in temperature w.r.t. to 46C

Yes, that is indeed followed by

> but that's an incorrect way of looking at it.

but that refers to a discussion of energy that follows. My whole point is that it's *NOT a 6.5% increase in temperature". OP's point seems to be that we shouldn't be considering the increase in temperature, but rather the increase in energy needed. That's fine. No objections. I'm just saying that the statement about the increase in temperature is also wrong.


> Kelvin is arbitrarily scaled.

Percentages are unitless, you're making a trivial observation that didn't need to be said.

I conclude that you lack the appropriate education to discuss this subject.


> Percentages are unitless, you're making a trivial observation that didn't need to be said.

My original observation was that Celsius and Fahrenheit are arbitrarily shifted, and that matters. Then you countered that Kelvin is arbitrary too, to which I write that it is only arbitrarily scaled, and that is fine (of course, for the exact trivial reason that you point out).

If your best argument is that I made a correct but trivial statement in addition to my main point, then I don't think there's much more to be had from this discussion.

I bid you farewell.




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