A brick wall \(\left( {k = 0.9\frac{W}{{mk}}} \right)\) of thickness 0.18 m separates the warm air in a room from the cold ambient air. On a particular winter day, the outside air temperature is -5°C and the room needs to be maintained at 27°C. The heat transfer coefficient associated with outside air is \(20\frac{W}{{{m^2}K'}}\). Neglecting the convective resistance of the air inside the room, the heat loss, in (W/m2), is

A brick wall \(\left( {k = 0.9\frac{W}{{mk}}} \right)\) of thickness

1.	A brick wall \(\left( {k = 0.9\frac{W}{{mk}}} \right)\) of thickness 0.18 m separates the warm air in a room from the cold ambient air. On a particular winter day, the outside air temperature is -5°C and the room needs to be maintained at 27°C. The heat transfer coefficient associated with outside air is \(20\frac{W}{{{m^2}K'}}\). Neglecting the convective resistance of the air inside the room, the heat loss, in (W/m2), is
A.	88
B.	110
C.	128
D.	160
Answer» D. 160

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