1. A window is 2.1 m high and 4.2 m long. A horizontal diffuse reflector is placed in front of the window. It is hinged at the bottom edge of the window so that when raised to a vertical position against the window it just covers the window. During daylight hours, the reflector is lowered to its horizontal position. Radiation data for an hour are I = 1.61 MJ/m2,la = 0.33 MJ/m²,l, = 1.28 MJ/m², and R, = 2.31. (a) If the (diffuse) reflectance of the reflector is 0.85, what will be the total radiation per %3D %3! %3D unit area on the window? (b) If the diffuse reflectance drops to 0.7, what will be the total radiation per unit area on the window?

1. A window is 2.1 m high and 4.2 m long. A horizontal diffuse reflector is placed in front of the window. It is hinged at the bottom edge of the window so that when raised to a vertical position against the window it just covers the window. During daylight hours, the reflector is lowered to its horizontal position. Radiation data for an hour are I = 1.61 MJ/m2,la = 0.33 MJ/m²,l, = 1.28 MJ/m², and R, = 2.31. (a) If the (diffuse) reflectance of the reflector is 0.85, what will be the total radiation per %3D %3! %3D unit area on the window? (b) If the diffuse reflectance drops to 0.7, what will be the total radiation per unit area on the window?

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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