Timeline for Emissivity and thermal equilibrium
Current License: CC BY-SA 3.0
3 events
| when toggle format | what | by | license | comment | |
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| Apr 22, 2013 at 10:49 | comment | added | John Rennie | In the link you mention, the items in the basement are not all at the same temperature. That's because the emissivity is a function of wavelength and the emissivity at the wavelength of visible light is not the same as the emissivity of the IR radiation at the cellar temperature. This is why a greenhouse heats up in sunlight, and the same effect will happen to a lesser extent for the items in the basement. | |
| Apr 22, 2013 at 10:26 | comment | added | Peter Webb | Thankyou both for your explanations. Thank you in particular for a the diagram and clear explanation of why E+R=1 matters. I am certain you are correct; it exactly explains what happens. I know this isn't a chat forum, but I googled first and found talkingphysics.wordpress.com/2012/11/24/… which claims that imaging cameras work differently, for example the Elmo photograph in his basement, where I suspect his basement was not in thermodynamic equilibrium. | |
| Apr 22, 2013 at 9:17 | history | answered | John Rennie | CC BY-SA 3.0 |