mroussel at alchemy.chem.utoronto.ca (Marc Roussel) writes:
>In article <1994Jan5.170448.3190 at aber.ac.uk> hrs at aber.ac.uk>(Herbert Martin Sauro) writes:
>>What happens if a thermometer is put in a vacuum that is bathed in
>>photons? Does the thermometer register a reading or not? (I think it
>>must do).
>The temperature of the vacuum is the temperature of a
>thermometer in radiative equilibrium with it. By a "cold" vacuum I
>meant one with a low temperature compared to the initial temperature of
>our measuring device.
So. Photons are thermal energy when they exist in a closed system.
Paul Schlosser wrote earlier that ``photons are not *thermal* energy;
i.e., absorbing a photon does not cool the surrounding medium the way
a "truly" endothermic reaction will.'' But surely they cool
something? The sun loses heat by losing photons, no? So can't we say
that things gain heat when they gain photons?
... John Woods
--
"
Forsan et haec olim meminisse iuvabit (Virgil)
[approx] Tr: The time may come when we will look back on these days and laugh
"
