Q2/ A thermopane window consists of two pieces of glass 7 mm thick that enclose an air space 7mm thick. The window separates room air at 20°C from outside ambient air at -10°C. Theconvection coefficient associated with the inner (room-side) surface is 10 W/m? K.If the convection coefficient associated with the outer (ambient) air is 80 W/m? K, what isthe heat loss through a window that is 0.8 m long by 0.5 m wide? Neglect radiation,f kglass = 1.4W/m-K: kair =0.024S W/m K)-Window, 0.8 m x 0.5 mGlassAir!Tmi= 20 °Chi = 10 Wim2 KAir11 L=0.007 mTo=-10 °Cho = 80 W/m2-KAir

T∞i=20°C, hi=10 Wm2KL=L1=L2=L3=.007 mA=.8×.5=.4 m2Kg=1.4 WmK and Kair=.0245 Wm Kh0=80 Wm2K,T∞0=-10°C…

Q2/ A thermopane window consists of two pieces of glass 7 mm thick that enelose an air space 7 mm thick. The window separates room air at 20°C from outside ambient air at -10°C. The convection coeflicient associated with the inner (room-side) surface is 10 Wim2 K. If the convection coefficient associated with the outer (ambient) air is 8o W/m2 K, what is the heat loss through a window that is 0.8 m long by 0.5 m wide? Neglcct radiation,f kglass = 1.4 W/m-K: kair -0.0245 W/m-K] Window, 0.8 m x 0.5 m Glass FL+L- Air| Taj= 20 °C hi = 10 W/m2 K Air I L=0.007 m T=-10 °C ho = 80 W/m2-K Air

Q2/ A thermopane window consists of two pieces of glass 7 mm thick that enelose an air space 7 mm thick. The window separates room air at 20°C from outside ambient air at -10°C. The convection coeflicient associated with the inner (room-side) surface is 10 Wim2 K. If the convection coefficient associated with the outer (ambient) air is 8o W/m2 K, what is the heat loss through a window that is 0.8 m long by 0.5 m wide? Neglcct radiation,f kglass = 1.4 W/m-K: kair -0.0245 W/m-K] Window, 0.8 m x 0.5 m Glass FL+L- Air| Taj= 20 °C hi = 10 W/m2 K Air I L=0.007 m T=-10 °C ho = 80 W/m2-K Air

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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