On Sunday, August 9, 2015 at 2:59:10 PM UTC+1, Alastair wrote:
On Sunday, 9 August 2015 07:30:58 UTC+1, wrote:
On Thursday, 6 August 2015 15:52:09 UTC+1, Alastair wrote:
Dawlish,

On Page 576 of University Physics with Modern Physics, Technology Update, Thirteenth Edition (2010), which continues to set the benchmark for clarity and rigor combined with effective teaching and research-based innovation, they write:

"Radiation. Heat transfer by radiation is important in some surprising places. A premature baby in an incubator can be cooled dangerously by radiation if the walls of the incubator happened to be cold, even when the air in the incubator is warm. Some incubators regulate the temperature measuring the baby's skin ..."

Hot objects radiate heat which warms adjacent objects. Cold objects radiate cold which cools adjects objects. The latter is difficult to demonstrate because it is more difficult to maintain a constant cold temperature than a high temperture. The latter is easy using electrical heating. However, holding a thermnometer over an object taken from a freezer will cause the temperature shown to drop.

I hope you will now realise that you are wrong, will apologise and admit your mistake. Cold radiation does exist.

Cheers, Alastair.

There is no such thing in Physics as "cold" - just lack of heat.

I am not saying "cold" exists. I am saying "cold radiation" exists, in the same way cold water exists.

Everything radiates heat, even a block of ice, the intensity of heat radiation being proportional to the 4th power of the Absolute Temperature (Stefan-Boltzmann Law). So if a body is in cold surroundings it radiates more heat than it gets back and so is cooled. You could look at that as "cold radiation"; all this argument is really just one of semantics.

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Not as far as Dawlish is concerned. He doesn't believe in cold radiation. Perhaps he should have cold water poured over his head.

Cheers, Alastair.

Not just me. Alastair, every single person with even only the basics of an education in physics understands simple thermodynamics and knows that cold radiation is impossible.

You have demonstrated clearly that you don't understand this and I can assure you that is not my fault.