Two concentric spheres of diameter D = 0.9 m and D2 = 1.2 m are separated by an air space and have surface temperatures of T = 390 K and T2 = 300 K. (a) If the surfaces are black, what is the net rate of radiation exchange between the spheres, in W? 912 = i w (b) What is the net rate of radiation exchange between the surfaces if they are diffuse and gray with e = 0.5 and ez = 0.05, in W? 912 = i (c) What is the net rate of radiation exchange if D2 is increased to 20 m, with e2 = 0.05, e1 = 0.5, and D = 0.9 m, in W? 912 (d) What is the net rate of radiation exchange if the larger sphere behaves as a black body (€2 = 1.0) and with e1 = 0.5, D2 = 20 m, and D = 0.9 m, in W? 912 =

Two concentric spheres of diameter D = 0.9 m and D2 = 1.2 m are separated by an air space and have surface temperatures of T = 390 K and T2 = 300 K. (a) If the surfaces are black, what is the net rate of radiation exchange between the spheres, in W? 912 = i w (b) What is the net rate of radiation exchange between the surfaces if they are diffuse and gray with e = 0.5 and ez = 0.05, in W? 912 = i (c) What is the net rate of radiation exchange if D2 is increased to 20 m, with e2 = 0.05, e1 = 0.5, and D = 0.9 m, in W? 912 (d) What is the net rate of radiation exchange if the larger sphere behaves as a black body (€2 = 1.0) and with e1 = 0.5, D2 = 20 m, and D = 0.9 m, in W? 912 =

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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