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And the best part is...And the best part is...Posted Oct 6, 2007 14:11 UTC (Sat) by richo123 (guest, #24309)In reply to: And the best part is... by rsidd Parent article: Laptop With a Mission Widens Its Audience (The New York Times)
Yes temperature is proportional to the kinetic energy PER MOLECULE. It isn't proportional to energy because if the energy is put into spinning the molecule rather than making it move that isn't counted in the temperature.
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And the best part is... Posted Oct 6, 2007 16:58 UTC (Sat) by rsidd (subscriber, #2582) [Link] Still wrong. Rotational kinetic energy certainly depends on the temperature, in the same way translational kinetic energy does, for a classical system. (That is, on average it is 1/2 kT for each degree of freedom that appears quadratically in the energy, including rotational degrees of freedom. Here k is the Boltzmann constant.)
Again, temperature is not proportional to energy. Temperature is the inverse of (dS/dE) where the derivatives are partial derivatives with other state variables constant. This happens to be proportional to the average energy for a classical ideal gas, and for other systems where the equipartition theorem applies. For other systems this does not apply. And even if the laptop battery's temperature were proportional to its energy (what energy? Energy consumption? Energy emitted? Energy stored?) what does it mean to say "it runs at a tenth the temperature"?
And the best part is... Posted Oct 6, 2007 17:14 UTC (Sat) by nix (subscriber, #2304) [Link] It's obvious what it means... you can only use it on Neptune and pointsfurther out; any further in and it overheats.
HTH, HAND, etc, &c, usw...
And the best part is... Posted Oct 6, 2007 18:32 UTC (Sat) by drag (subscriber, #31333) [Link] > what does it mean to say "it runs at a tenth the temperature"?
It says: 'I am a typo'. Or at least that is what it says to me.
It probably means it runs at a tenth of the temperature when compared to other convientional laptop batteries. That wouldn't be hard to do as other laptops typically draw much more current and require much larger batteries. The faster you draw current the hotter the batteries get (and the more expensive then need to be to manage the power draw without damage). This combined with whatever chemistry or circuity improvement the XO does then one tenth the temperature would be easy to to imagine.
:)
And the best part is... Posted Oct 6, 2007 19:25 UTC (Sat) by richo123 (guest, #24309) [Link] Sorry you are correct. My statement is true only for a monatomic ideal gas.
And the best part is... Posted Oct 7, 2007 15:39 UTC (Sun) by tialaramex (subscriber, #21167) [Link] I'd argue that it can only mean that while an ordinary laptop battery is intended for use at around room temperature (say 290-330 K) these new batteries are intended for use at around 30 K, which means you will require a source of liquid helium to cool it in a practical way. No doubt this will be very inconvenient for its users in developing nations.
That is, it's nonsense, and it's a shame that
the writer apparently didn't know any better
And the best part is... Posted Oct 7, 2007 16:05 UTC (Sun) by khim (guest, #9252) [Link] Actually "practically no-one reading will think there's anything odd about it" because there are nothing odd about it. Any non-geek reader will understood that the talk is about temperature difference between ambient temperature and temperature of battery, not about temperature of battery per se. There were a lot of talks about "hot" Prescott or "cool" Core2 - and temperature there is meant in exactly the some way, so it's not something new or strange. Some guys will note that this huge difference mostly stem from low power consumption of laptop, not from superiority of the battery itself (mobile phones also have pretty coll batteries while using conventional chemistry). And this will be all... Geeks, on the other hand, will nitpick to the death...
And the best part is... Posted Oct 7, 2007 17:20 UTC (Sun) by tialaramex (subscriber, #21167) [Link] because there are nothing odd about it
Nothing about it /appears/ to be odd if you're scientifically illiterate, which most of the readers and practically all the writers are. We're agreed thus far. Newspapers routinely publish nonsense about science or technology without any comment. Suppose they'd made a similarly significant mistake, but in a section of the paper that some of the readers know something about, like the Sports section.
Tiger Woods scored two bogeys in a row, picking up the points needed to win the match.
It wouldn't take five minutes for sports fans to mob the newspaper's corrections desk. Tiger won with two birdies, not bogeys, you imbeciles. Call yourselves a newspaper? Has the guy writing your sports columns ever played golf? etc.
This is not about geeks, you don't need to be a technology "geek" to know that the sentence about temperature is nonsense. Remember this is not a blog, there's an editorial process that's supposed to screen out typos and stupid mistakes. But for Sci/Tech articles that process might as well not exist (sometimes it even makes things worse as a sub-editor who has never heard of the "Watt hour" changes it to "Watts per hour" for example).
The Language Log ran an article about this sort of phenomenon recently. Apparently one of the remaining unintegrated tribes doesn't have numeracy. When outsiders offer to teach it to them they can't see the benefit, even though they are traders and the inability to count must interfere constantly. The Language Log article argues that our culture as a whole has the same attitude towards useful post-numeracy skills, and our justifications are equally foolish.
And the best part is... Posted Oct 28, 2007 13:17 UTC (Sun) by kreutzm (subscriber, #4700) [Link] While we're at physics, could you quickly pass me the recipie to get *liquid* helium at 30 K? Thanks!
And the best part is... Posted Oct 28, 2007 17:15 UTC (Sun) by evgeny (guest, #774) [Link] In order to cool something down to 30K, one needs a cooling medium with a _lower_ temperature; so what's wrong with using liquid helium (< 4.2K) for that purpose??
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