QI/ Consider a 5-m-high, 8-m-long, and 0.22-m-thick wall whose representative crosssection is as given in the figure. The thermal conductivities of various materials used, inW/m."C, are kA = kF = 2, kB = 8, kC = 20, kD = 15, and kE= 35. The left and right surfacesof the wall are maintained at uniform temperatures of 300°C and 100°C, respectively.Assuming heat transfer through the wall to be one-dimensional, determine (a) the rate ofheat transfer through the wall; (b) the temperature at the point where the sections B, D, andE meet; and (c) the temperature drop across the section F.100°C300°CD4 cm6 стстC6 cm4 cm8 m1 cm5 ст 10 ст 16 ст Q2/ The wall of a refrigerator is constructed of fiberglass insulation (k=0.035 W/ m. C)sandwiched between two layers of 1-mm-thick sheet metal (k-15.1 W/m.°C). Therefrigerated space is maintained at 3°C, and the average heat transfer coefficients at theinner and outer surfaces of the wall are 4 W/m2.C and 9 W/m2.°C, respectively. Thekitchen temperature averages 25°C. It is observed that condensation occurs on the outersurfaces of the refrigerator when the temperature of the outer surface drops to 20°C.Determine the minimum thickness of fiberglass insulation that needs to be used in the wallin order to avoid condensation on the outer surfaces.Sheet metalKitchenRefrigeratedairspace3°C25°CInsulation10°C1 mmmm

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QI/ Consider a 5-m-high, 8-m-long, and 0.22-m-thick wall whose representative cross section is as given in the figure. The thermal conductivities of various materials used, in W/m."C, are kA = kF = 2, kB = 8, kC = 20, kD = 15, and kE= 35. The left and right surfaces of the wall are maintained at uniform temperatures of 300°C and 100°C, respectively. Assuming heat transfer through the wall to be one-dimensional, determine (a) the rate of heat transfer through the wall; (b) the temperature at the point where the sections B, D, and E meet; and (c) the temperature drop across the section F.

QI/ Consider a 5-m-high, 8-m-long, and 0.22-m-thick wall whose representative cross section is as given in the figure. The thermal conductivities of various materials used, in W/m."C, are kA = kF = 2, kB = 8, kC = 20, kD = 15, and kE= 35. The left and right surfaces of the wall are maintained at uniform temperatures of 300°C and 100°C, respectively. Assuming heat transfer through the wall to be one-dimensional, determine (a) the rate of heat transfer through the wall; (b) the temperature at the point where the sections B, D, and E meet; and (c) the temperature drop across the section F.

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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