A cavity whose walls are held at 1900 K has a small hole, 1.00 mm in diameter, drilled in its wall. We have to find the rate at which energy is escaping through this hole from the interior of the cavity.

Solution:             Click For PDF Version

The total radiation power per unit area emitted from a cavity aperture is given by the Stefan-Boltzmann law, which states that

Therefore, the rate at which energy will escape from a hole of diameter 1.0 mm from a cavity whose walls are held at 1900 K will be