[Amps] Black Heat Shields

[gdaught6 at stanford.edu]

Mike wrote...

> Conservation of energy in the universe - materials absorb and radiate
> energy at the same rate.

No they don't.  An object in thermal equilibrium with its surroundings will absorb 
and radiate energy at the same rate.  

If it absorbs more than it radiates, it will heat up.  If it radiates more than it absorbs, it 
will cool down.  

Then, consider an incandescent filament... if you 'pump' energy into it (e.g. !^2 R 
heating) it will heat up until it is radiating as much as the energy being supplied.  Of 
course some of the (heat) energy will be conducted away, as well, not just radiated, 
and if the filament is in a tube, emitting electrons, the electrons will carry away some 
of the energy in the form of their kinetic energy, if the temperature is high enough 
that the electron's kinetic energy exceeds the metal's 'work function.'  

Things are always so complicated.  My simplification is:

Use a BIG blower, blow LOTS of air, and put headphones on so the fan noise doesn't 
bother you!  [You can paint the 'phones black if you like!]

73,

George T Daughters, K6GT
CU in the California QSO Party (CQP)
October 1-2, 2011