A question on heat transfer and blackbodys

AI Thread Summary
The discussion revolves around the relationship between heat transfer equations for blackbodies and the cooling process of materials. The first equation, representing radiation, describes the power emitted by a perfect blackbody, while the second equation pertains to convective heat transfer. The inquiry is whether applying the time derivative of the convective equation can yield a temperature function for a blackbody radiator cooling in a vacuum. Participants clarify that these two types of heat transfer are fundamentally different and cannot be directly equated. Ultimately, the conclusion is that the approach suggested may not be valid due to the distinct nature of radiation and convection.
pastro
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Hello,

I was wondering:
\frac{dQ}{dt} = \sigma A T^{4}
for a perfect blackbody.

Also
Q = mc\DeltaT

If I take the time derivative of the above equation, set it equal to the power emitted by a blackbody, and solve the resulting differential equation for temperature, does that give me the temperature with which a blackbody radiator of a given mass and material cools in vacuum as a function of time?

Just curious...

Thanks!
 
Last edited:
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Ummm, I doubt it.

Equation 1 is for, well, radiation.

Equation 2, as I understand it, is for convective heat transfer.

The two are not really the same thing.
 

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