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Re: Close but no cigar? again

I know. I promised no more remarks until I did my homework.

The Stefan-Boltzmann law of radiation is P = s T^4, where s (the
Stefan-Boltzmann constant, usually written as the greek lower-case
letter sigma) does indeed have the value 5.67 E-8 W/(m^2 K^4).  A
black-body surface absorbing a power of 7.5E5 W/m^2 (your number)
will be heated to an ultimate equilibrium temperature Teq at which
it will reradiate all the absorbed power.  Therefore,

                   7.5E5 = 5.67E-8 Teq^4  .

So Teq equals 1907 K, below the melting temperature of titanium
(2073 K) and well below the melting temperature of tungsten.

Unless I missed something, I believe you (I don't know who,
because I haven't yet learned to read these quotes of quotes of
quotes) equated power to energy in your calculation of no cigar.

Rex Finke