Two very large parallel metal plates are separated by a small vacuum gap. Plate 1 is in contact with liquid nitrogen at T₁ = 77 K; plate 2 is at room temperature, so T₂ = 300 K (see the figure). In order to reduce the heat loss by radiation, a third plate is inserted in the middle. The absorptivity of the middle plate is a=0.10 (i.e., it absorbs 10% of radiation). Both plates 1 and 2 are considered to be blackbody, and the absorptivity equals 1.0. (The Stefan-Boltzmann constant is o=5.67x10 W/(m²K)) Tm (a) Find the equilibrium temperature of middle plate Tm. (b) Find energy flux between T, and T2 plates if the middle plate is not inserted. (c) Find energy flux between T, and T2 plates at the presence of the middle plate. T₁

Two very large parallel metal plates are separated by a small vacuum gap. Plate 1 is in contact with liquid nitrogen at T₁ = 77 K; plate 2 is at room temperature, so T₂ = 300 K (see the figure). In order to reduce the heat loss by radiation, a third plate is inserted in the middle. The absorptivity of the middle plate is a=0.10 (i.e., it absorbs 10% of radiation). Both plates 1 and 2 are considered to be blackbody, and the absorptivity equals 1.0. (The Stefan-Boltzmann constant is o=5.67x10 W/(m²K)) Tm (a) Find the equilibrium temperature of middle plate Tm. (b) Find energy flux between T, and T2 plates if the middle plate is not inserted. (c) Find energy flux between T, and T2 plates at the presence of the middle plate. T₁

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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