Problem 2: A small object with an opaque, diffuse surface at a temperature of 500 K is suspended in a large furnace with walls at 2000 K. Assume that the

walls of the furnace provide a diffuse irradiation to the object at a black body temperature equal to the furnace wall temperature. The object's surface has a spectral hemispherical emissivity and absorptivity as given below. (a) Determine the total emissivity and total absorptivity of the object's surface. (b) Evaluate the net radiation heat flux at the surface. (c) Sketch the spectral emissive power distribution over all wavelengths for the object (see figure on p.799 of text, in Example 12.6), and also for a black body at the same temperature as the object.

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