Infrared Wavelength: Same Emission for All Materials?

[skikid]

Do different materials (i.e. granite, steel, water, etc.), all at the same temperature, emit the same infrared wavelength?

 

[zhermes]

Do different materials (i.e. granite, steel, water, etc.), all at the same temperature, emit the same infrared wavelength?

For the most part, yes. See 'kirchoff's[/PLAIN] law'

They will emit the same radiation if you think of them as perfect 'black bodies' (basically the simplest model of a thermal emitter). But materials are not perfect black bodies, and thus exhibit some differences in their spectra---largely from emission/absorption lines

 

[skikid]

Thank You.

 

[Naty1]

But they may not be observed [measured] as such when viewed from a distance, [redshift,blue shift] etc..