On 28.01.2012 00:24 Craig Weinberg said the following:
On Jan 27, 1:31 pm, John Clark<johnkcl...@gmail.com>  wrote:
On Thu, Jan 26, 2012 at 8:03 PM, Craig
Weinberg<whatsons...@gmail.com>wrote:

With the second law of thermodynamics, it seems like heat could
only dissipate by heating something else up.

The second law says that energy will tend to get diluted in space
over time, and heat conducting to other matter is one way for this
to happen but it is not the only way. Photons radiating outward in
all directions from a hot object is another way energy can get
diluted. But among many other things, you don't think photons, or
logic, exist so I doubt this answer will satisfy you.

It would satisfy me if I you had some examples, but I don't think
that you know the answer for sure. If a vacuum is a good insulator
(like a vacuum thermos) and a perfect vacuum, as far as I have been
able to read online, is a perfect insulator. Electricity and heat
pass from object to object, not from space to space. Please point out
any source you can find to the contrary. What little I find agrees
with vacuums being insulators of heat and electricity.

Graig,

Radiation does happen. If you need more detail, there is a nice free book from MIT

A Heat Transfer Textbook,  4th edition
John H. Lienhard IV, Professor, University of Houston
John H. Lienhard V, Professor, Massachusetts Institute of Technology

http://web.mit.edu/lienhard/www/ahtt.html

Some disadvantage is that it is thick but you go directly to Part IV Thermal Radiation Heat Transfer. Vacuum is a good insulator but thermal radiation gets through.

It is pretty important for example to include radiation in the case of free convection as it may account up to 40% of heat transfer in this case.

Evgenii

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