Imagine a diamond sphere radius of 1 cm traveling in space far from any heat sources. Embedded in the center of the sphere is a magic heater that can produce 0.3 W for an indefinite amount of time.(adsbygoogle = window.adsbygoogle || []).push({});

If the emissivity of the surface is zero, what temperature does the sphere reach? Why?

The answer is infinite temperature. I don't understand this. If emissivity is zero, doesn't that mean the body doesn't emit OR absorb any heat? I would think that the answer is that it would not reach any temperature... Can somebody explain to me why it would be infinite temperature? Is it because the time factor?

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# Homework Help: Question about black bodies, emissivity.

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