Cold Radiation
On Monday, August 10, 2015 at 9:06:23 PM UTC+1, Alastair wrote:
On Monday, 10 August 2015 18:14:28 UTC+1, Dawlish wrote:
On Monday, August 10, 2015 at 6:07:01 PM UTC+1, Alastair wrote:
"RedAcer" wrote in message
...
On 10/08/15 16:53, RedAcer wrote:
On 10/08/15 15:12, Alastair McDonald wrote:
"RedAcer" wrote in message
The hotter body will cool anyway whether the colder body is there or
not. The radiation from the colder body means that the hot body will
cool more slowly that it would have done if the cold body weren't
there.
It is not 'cold' radiation as you keep insisting. It does not cool the
hot body, it warms it up.(I'm assuming no background bodies or source
of
radiation)
There is always background radiation of one type or another. Think
about
it. You are either surrounded by walls, or by the earth and sky, or by
cosmic background radiation. Describe a real situation where it does not
exist.
We are all trying to explain some physics to you. The way that it's done
(in any physics class/book) is to concentrate on the salient features of
interest in the system and ignore/minimise other 'smaller' effects.
Assume we doing the experiment out in space where the CMBR is at 2.3K.
Let the cold body be at 200K and the hot at 300K. OK.
Terms of in the SB equation are proportional to T^4 and so can easily be
ignored in a first approximation.
Last sentence not very clear, should be:-
"Terms in the SB equation are proportional to T^4 an so the CMBR can
ignored in a first approximation."
You are making the same mistake as Alan LeHun in the Four Question thread.
You have not got a two body system. It is a three bodies when you include
the CMBR. In that case the main source of cold radiation is the coldest
body - the CMBR. It is not the cooler of the two bodies. If you then
approximate the CMBR, which is the source of the cold radiation, to zero,
then of course the cold radiation does not exist. But that is because you
have approximated it to zero. You can't just approximate numbers to zero,
particulary if they are divisors, which of course they aren't in this case.
I think you have a bit more to learn before you try to teaching me.
Cheers, Alastair.
Everyone is making the same 'mistake' as each other - not believing you about 'cold radiation', as its existence would mean re-writing the laws of thermodynamics.
Don't you think that is slightly odd? No-one in science would back you, yet you think you are completely right.
That makes you a genius, well worthy of the Nobel prize, or a completely deluded idiot, wouldn't you agree, Alastair?
Pointing out the simple fact that radiation from a colder object will cool a warmer one is only common sense. Considering it was demonstrated by Prof. Pictet 250 years ago, I can't see why I deserves any praise.
OTOH, the stick I have received from all on this newgroup for pointing out that fact does deserve an apology, but the possiblity of that happening can probably be approximated to zero :-(
Yawn. For the third time from me and for the umpteenth time from others, Pictet's experiment was explained a century ago, without any invoking this silly 'cold radiation'.
You, however, do not wish to acknowledge this fact. No-one still believes what picket's experiment appeared to show, over 200 years ago, except you. Time you recognised that.
Take Pictet away - and we have - and you have absolutely no scientific basis whatsoever for this nonsense.
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