[Amps] Fan for SB220

[Ken Brown]

> To further prove my point, you have a black car and a white car out in 
> the sun on a hot day.
> You know the black car is going to be hotter, but why is this when black 
> is apparently such a good radiator that it should just radiate all that 
> excess heat right out of that car, as quick as its absorbing it?.
>
>   
Radiant heat (which is essentially light, mostly at longer than visible 
wavelengths) travels from the higher temperature mass ( sun for instance 
) to the lower temperature mass (car for instance) A flat black 
automobile will collect radiant heat from the sun more effectively than 
a shiny white car. When the sun goes down, you can take two cars heated 
up to the same temperature out under the cold (about 3 to 4 Kevin ) 
clear sky and the heat flow will be in the opposite direction than it 
was in the daytime. The flat black car will lose heat faster than the 
shiny white car.

Black absorbs AND radiates heat more efficiently.


> Because its not a good radiator, but it pretty good at absorbing the 
> sunlight radiated heat  increasing the temperature within. 
WRONG!
> The surface 
> temperature is damn hot and when you drive the black car down the road, 
> the air passing over the car cools it down due to COVECTION.
>   
When the sun is down it will also lose heat by radiation to the cold 
expanse of space faster than the white car.
> Things don't radiated of their own accord without a energy source,
The energy source is the heat in the object, and every object that has a 
temperature higher than absolute zero radiates heat.Whether the net heat 
flow is absorbing or radiating depends on the relative temperatures of 
the objects it "sees". It is always absorbing and radiating, and black 
does both better.
>  and 
> there is a colour spectrum for different types of radiation, ie: infra 
> red which you see from the 3-500z is radiated heat, white light 
> composing all the colours within of various luminous wavelengths. Ultra 
> violet etc, the list goes on.
>   
You do not have to be able to see it for it to be radiating heat. Our 
eyes do not respond very well to IR.
> Please let me know what the wavelength is of radiated heat from black?
>   
 From wikipedia:
>
> *Infrared (IR)* light is electromagnetic radiation 
> <http://en.wikipedia.org/wiki/Electromagnetic_radiation> with a 
> wavelength <http://en.wikipedia.org/wiki/Wavelength> between 0.7 and 
> 300 micrometres <http://en.wikipedia.org/wiki/Micrometre>, which 
> equates to a frequency range 
> <http://en.wikipedia.org/wiki/Frequency_range> between approximately 1 
> and 430 THz <http://en.wikipedia.org/wiki/THz>.^[1] 
> <http://en.wikipedia.org/wiki/Infrared#cite_note-0>
>
> IR wavelengths are longer than that of visible light 
> <http://en.wikipedia.org/wiki/Visible_light>, but shorter than that of 
> terahertz radiation <http://en.wikipedia.org/wiki/Terahertz_radiation> 
> microwaves <http://en.wikipedia.org/wiki/Microwaves>.