"Radiant heat" is a non-scientific, superstitious concept. There is radiation and there is heat. Two different things that can transmute.
"Radiant heat" is a non-scientific, superstitious concept. There is radiation and there is heat. Two different things that can transmute.
Nonsense. What you feel from the sun is a broad spectrum from IR to visible to UV that is converts to heat when absorbed by your tissues. Visible light is just as sensible as infrared, as heating upon absorption.
Infrared and visible EM are alike in regards to heating. Infrared is not "radiant heat", although it radiates and converts to heat upon absorption, but it is no different from visible light in that regard.
"Radiant heat" is a non-scientific concept, although it at least phenomenologically descriptive. The idea that infrared is somehow different from visible light in regards to "radiant heat" is a pure fallacy.
That's true. Buy, typically, when talking about space heaters, "where you want it" is usually in the room where you place the heater. That's certainly the case in the context of this discussion.
Any and all energy 'consumed' by an electric space heater is dissipated as heat in the room in which it is placed. They are 100% efficient, by definition. That's why efficiency ratings are not required on electric space heaters (didn't you ever wonder about that?). One heater that is deemed 'better' than another is better only in terms of bells, whistles, and/or durability (although consumers frequently pay a hefty premium for slick marketing).
"Why don't we just ask Osama bin Laden? Uh, Osama Obama!" -- Ted Kennedy
Actually light is measured in Lumens...... not watts......
I agree with that!
And all I did was ask a simple question. :-)
Actually Lumens are a complicated unit.
Duane
Infrared is electromagnetic radiation at frequencies just below the visible spectrum (next to red). That is NOT heat. The fact that EM is constantly being converted to and from heat in no way makes them the same thing.
I don't know much about PV panels, but I do know that 100% efficiency doesn't exist. I do remember hearing that PV devices were at most about 10% efficient. What is the waste product?
Which explains why I wouldn't say that it is.
Do you have any specific information on what happens to it, then?
Strange, and almost certainly false. Light (apparently "visible light" here) and Infrared are both EM radiation, and very similar. Infrared is just slightly lower in frequency (like ultraviolet is on the other side of the visible spectrum).
Ever seen one of these?
Bingo.
Not so much by definition as by conservation of energy.
That's why efficiency ratings are not
Is that a seasonal rate? I don't see any time parameters associated with it. PG&E changes rates so often that they are very clear about the effective dates of the rate sheets ;-)
Propane is $1.95 per gallon.
Funny we can photograph infrared heat from people's bodies and other warm objects even though it isn't heat.
So you know why the vanes turn then?
What happens when you put it in the freezer?
Joe Fischer
IDIOT
There is (still) no such thing as "infrared heat". Infrared radiation is produced by warm objects. Heating these objects further produces more visible light (as seen in flames and heating elements, and in sparks too).
Photographic film, as well as CCD arrays in digital cameras, is sensitive to electromagnetic radiation in the infrared range.
There is no such thing as a Mark even though you keep beaking off.
Yeah, it turns due to the reflected photons (in theory since photons are on therom anyway). The spindle turns towards the black faces and away from the white ones in light.
Sorry, that is incorrect, while it is possible to make a radiometer that turns from reflected photons like a solar sail is supposed to accelerate due to radiation pressure of reflected photons, the Crook's radiometer works because the black side gets warm and the gas press in the thing is low enough the mean free path is long enough to allow the molecules to bounce off the black side with more energy than they had before bouncing.
Wrong, if you would have tried it in the freezer, it will turn towards the black faces and away from the white ones in the dark for a little while until the vanes cool off.
But in light, it turns toward the white faces due to the black side heating the gas molecules.
All you have to do is LOOK, and PAY ATTENTION, instead of just assuming, and that gives you first hand knowledge that will help more than reading books.
Joe Fischer
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