During a winter day, the window of a patio door with a height of 1.8 m and width of 1.0 m shows a frost line near its base, hence the temperature of the window is T, = 0°C. The room wall and air temperatures are 15°C. Determined to reduce the $7 per week cost associated with heat loss through their patio window by convection and radiation, the tenants cover the inside of the window with a 50-mm-thick sheet of extruded insulation. Because they are not very handy around the house, the insulation is installed poorly, resulting in an S= 5.00-mm gap between the extruded insulation and the window pane, allowing the room air to infiltrate into the space between the pane and the insulation. Determine the magnitude of the rate of heat loss through the window, in W, and associated weekly cost, in $, with the ill-fitting insulation in place for a utility rate of 0.18 $/kW-h.. The insulation will significantly reduce the radiation losses through the window. Losses will be due almost entirely to convection. |q| = Cost = i 1555.82 $i 34.76 Window, 1.8 mx 1.0 m W

During a winter day, the window of a patio door with a height of 1.8 m and width of 1.0 m shows a frost line near its base, hence the temperature of the window is T, = 0°C. The room wall and air temperatures are 15°C. Determined to reduce the $7 per week cost associated with heat loss through their patio window by convection and radiation, the tenants cover the inside of the window with a 50-mm-thick sheet of extruded insulation. Because they are not very handy around the house, the insulation is installed poorly, resulting in an S= 5.00-mm gap between the extruded insulation and the window pane, allowing the room air to infiltrate into the space between the pane and the insulation. Determine the magnitude of the rate of heat loss through the window, in W, and associated weekly cost, in $, with the ill-fitting insulation in place for a utility rate of 0.18 $/kW-h.. The insulation will significantly reduce the radiation losses through the window. Losses will be due almost entirely to convection. |q| = Cost = i 1555.82 $i 34.76 Window, 1.8 mx 1.0 m W

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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