Two concentric spheres of diameter D = 0.8 m and D2 T1 = 410 K and T2 = 300 K. = 1.2 m are separated by an air space and have surface temperatures of (a) If the surfaces are black, what is the net rate of radiation exchange between the spheres, in W? 912 = W (b) What is the net rate of radiation exchange between the surfaces if they are diffuse and gray with & = 0.5 and ɛ2 = 0.05, in W? 912 = W (c) What is the net rate of radiation exchange if D2 is increased to 20 m, with ɛ2 = 0.05, ɛj = 0.5, and D = 0.8 m, in W? 912 = i W

Two concentric spheres of diameter D = 0.8 m and D2 T1 = 410 K and T2 = 300 K. = 1.2 m are separated by an air space and have surface temperatures of (a) If the surfaces are black, what is the net rate of radiation exchange between the spheres, in W? 912 = W (b) What is the net rate of radiation exchange between the surfaces if they are diffuse and gray with & = 0.5 and ɛ2 = 0.05, in W? 912 = W (c) What is the net rate of radiation exchange if D2 is increased to 20 m, with ɛ2 = 0.05, ɛj = 0.5, and D = 0.8 m, in W? 912 = i W

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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