2. Two large plates parallel plates having emissivities of 0.4 and 0.6 are maintained at temperatures of 900 K and 300 K, respectively. A radiation shield having an emissivity of 0.06 on both sides is placed between the two plates. Calculate (a) the heat transfer rate per unit area if the shield was not present; (b) the heat transfer rate per unit area with the shield present; (c) the percent decrease in heat transfer if the shield is in place.

2. Two large plates parallel plates having emissivities of 0.4 and 0.6 are maintained at temperatures of 900 K and 300 K, respectively. A radiation shield having an emissivity of 0.06 on both sides is placed between the two plates. Calculate (a) the heat transfer rate per unit area if the shield was not present; (b) the heat transfer rate per unit area with the shield present; (c) the percent decrease in heat transfer if the shield is in place.

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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