The heat flux passing through a plane wall of a well-insulated house is q = 2.5 Btu/hr-ft^2 when the temperature of the inside-facing surface of the wall is 71.3 F, and the outside-facing surface is at 16 F.
(a) What is the thermal reistance r of the wall?
(b) What is the thickness of a pane of window glass (cellular glass) that would transmit the same heat flux q as that passing through the wall? The temperatures T(hi) and T(lo) are the same for the wall and the glass.