A 10-in-thick, 40-ft-long, and 20-ft-high wall is to be constructed using 9-in-long solid bricks (k = 0.50 Btu/h·ft"F) of cross section 7 in x 7 in, or identical size bricks with nine square air holes (k = 0.02 Btu/h-ft°F) that are 9 in long and have a cross section of 1.5 in x 1.5 in. There is a 0.5-in-thick plaster layer (k = 0.15 Btu/h-ft-"F) between two adjacent bricks on all four sides and on both sides of the wall. The house is maintained at 80°F and the ambient temperature outside is 35°F. Taking the heat transfer coefficients at the inner and outer surfaces of the wall to be 2.0 and 4.0 Btu/h-ft. "F, respectively, determine the rate of heat loss transferred through the wall constructed of (a) solid bricks and, (b) bricks with air holes. Air channels 1.5 in x 1.5 in x 9 in 0.5 in 7 in 0.5 in Plaster Brick 0.5 in 0.5 in 9 in-

A 10-in-thick, 40-ft-long, and 20-ft-high wall is to be constructed using 9-in-long solid bricks (k = 0.50 Btu/h·ft"F) of cross section 7 in x 7 in, or identical size bricks with nine square air holes (k = 0.02 Btu/h-ft°F) that are 9 in long and have a cross section of 1.5 in x 1.5 in. There is a 0.5-in-thick plaster layer (k = 0.15 Btu/h-ft-"F) between two adjacent bricks on all four sides and on both sides of the wall. The house is maintained at 80°F and the ambient temperature outside is 35°F. Taking the heat transfer coefficients at the inner and outer surfaces of the wall to be 2.0 and 4.0 Btu/h-ft. "F, respectively, determine the rate of heat loss transferred through the wall constructed of (a) solid bricks and, (b) bricks with air holes. Air channels 1.5 in x 1.5 in x 9 in 0.5 in 7 in 0.5 in Plaster Brick 0.5 in 0.5 in 9 in-

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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