A brick wall (k = 0.9 W/mK) 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 W/m2K. Neglecting the convective resistance of the air inside the room, the heat loss, in (W/m2), is

A brick wall (k = 0.9 W/mK) of thickness 0.18 m separates the warm air

1.	A brick wall (k = 0.9 W/mK) 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 W/m2K. 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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