Posted by SLS on September 4, 2006, at 19:36:05
In reply to Re: Biopsychosocial vs Biological Reductionism, posted by finelinebob on September 4, 2006, at 17:30:48
> > cold as blue glacial ice = low energy (temperature)
> >
> > hot as red glowing metal = high energy (temperature)
> >
> > We have blue to signify cold water and red to signify hot. I don't know if these color associations are somehow intuitive or simply taught culturally. Fire is rarely blue, but very often yellow, orange, and red. It is interesting that radiant heat is conveyed in the infrared region of the spectrum. The decision to design the computer program to essentially "reverse" the spectral portrayal of energies in is interesting. It works sort of like a weather map.
>
> It is completely cultural.
>
> I'd imagine ice thick enough to appear green to blue is scattering light for reasons similar to why the sky is blue.
>
> Of course, the word "heat" and how it is used is just a cultural artifact in itself, but infrared radiation happens to have wavelengths larger but similar to molecular sizes so when some IR "hits" an object, the molecules get a bit more energy to move around and that motion is what we call heat.
>
> Ultraviolet light is also pretty close, but on the small end in terms of wavelength. Because it's smaller, it can pass through some materials without really affecting them, get absorbed then spit back out as something else. White clothes glowing under UV light means that non-visible radiation is being re-emitted as visible light ... then there's the photoelectric effect -- Einstein's Nobel Prize came from his work on this -- where UV light hitting metal can create an electric charge or current flow.
>
> As for flames being blue -- any welder or chemist can tell you that a blue flame has a higher temperature (typically from more efficient combustion of a gas, like with an acetylene torch or Bunsen burner) than red flames. Same thing if you have a gas stove. But other than gas stoves and pilot lights on water heaters, I can't think of many common situations where combustion is efficient enough to raise temperatures that high.Yeah. I forgot about Bunsen burners. It's been too long since school.
:-)
- Scott
poster:SLS
thread:680731
URL: http://www.dr-bob.org/babble/20060901/msgs/683119.html