A thermal window consisting of two panes of 0.25" glass (R-value 0.08 hr · ft2. °F/BTU each), separated by a layer of air 0.75" thick is now used as a horizontal window in the ceiling (a skylight) of an air conditioned room. Find its R-value in the summer, when the outside is warmer than the inside, and in the winter, when the inside is warmer than the outside (in hr · ft2. °F/BTU). (Assume that the air is moving outside the window.) R (summer) _hr ft2. °F/BTU R (winter) hr ft2. °F/BTU

A thermal window consisting of two panes of 0.25" glass (R-value 0.08 hr · ft2. °F/BTU each), separated by a layer of air 0.75" thick is now used as a horizontal window in the ceiling (a skylight) of an air conditioned room. Find its R-value in the summer, when the outside is warmer than the inside, and in the winter, when the inside is warmer than the outside (in hr · ft2. °F/BTU). (Assume that the air is moving outside the window.) R (summer) _hr ft2. °F/BTU R (winter) hr ft2. °F/BTU

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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