If the emissivity e varies with zenith angle according to e = E*cos(theta) where E is the emissivity normal to the surface. Would this surface be an isotropic source of radiation?(adsbygoogle = window.adsbygoogle || []).push({});

Well, since e varies with angle then the flux density must vary accordingly so the surface would radiate anistropically.

Anybody disagree?

Callisto

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# Emissivity e varies with zenith angle according to e = E*cos(theta)

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