A thermopane window consists of two pieces of glass 7 mm thick that enclose an air space 7 mm thick. The window separates room air at 20°C from outside ambient air at -10°C. The convection coefficient associated with the inner (room- side) surface is h= 10 W/m2. K. If the convection coefficient associated with the outer (ambient) air is h,= 80 W/m². K, what is the heat loss through a window that is 0.8 m long by 0.5 m wide? Neglect radiation, and assume the air enclosed between the panes to be stagnant. k, (glass) = 1.4 W/m.K, ka (air) = %3D 0.0245 W/m.K Window, 0.8 m x 0.5 m Glass FL+L+-L Air |I L= 0.007 m Air Teo =-10 °C ho = 80 W/m2-K Air Too.j = 20 °C h; = 10 W/m2•K %3D %3D

A thermopane window consists of two pieces of glass 7 mm thick that enclose an air space 7 mm thick. The window separates room air at 20°C from outside ambient air at -10°C. The convection coefficient associated with the inner (room- side) surface is h= 10 W/m2. K. If the convection coefficient associated with the outer (ambient) air is h,= 80 W/m². K, what is the heat loss through a window that is 0.8 m long by 0.5 m wide? Neglect radiation, and assume the air enclosed between the panes to be stagnant. k, (glass) = 1.4 W/m.K, ka (air) = %3D 0.0245 W/m.K Window, 0.8 m x 0.5 m Glass FL+L+-L Air |I L= 0.007 m Air Teo =-10 °C ho = 80 W/m2-K Air Too.j = 20 °C h; = 10 W/m2•K %3D %3D

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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