The thermal conductivity of the glass window is taken to be k = 0.8 Wm^-1"^@C^-1k=0.8Wm−1∘C−1. Let DeltaT be the temperature difference between the inner and outer surfaces
Heat conducted through the window Q_g=kA(DeltaT" ")/"Thickness of glass"
=>Q_g=(0.8xx2)/(0.75xx10^-2)DeltaT
The thermal conductivity of the walls is given to be twice of glass wool k_w = 2xx0.04 Wm^-1"^@C^-1.
Therefore, heat conducted through the walls Q_w=k_wA_w(DeltaT" ")/"Thickness of wall"
=>Q_w=(0.08xx10)/(13xx10^-2)DeltaT
Window to Wall Ratio=Q_g/Q_w=((0.8xx2)/(0.75xx10^-2)DeltaT)/((0.08xx10)/(13xx10^-2)DeltaT)
Given is the same temperature difference between them. Above expression reduces to
Q_g/Q_w=((0.8xx2)/0.75)/((0.08xx10)/13)
=>Q_g/Q_w=((0.8xx2)/0.75)xx(13/(0.08xx10))
=>Q_g/Q_w=34.dot6approx35
