Multiple Choice
A concrete wall of a cold storage room measures 3.0 m high,5.0 m wide,and 20 cm thick.The inside wall is to be covered by a layer of wood in order to reduce the rate of heat flow through the wall by 90 percent.The inner surface of the wooden wall is maintained at -10°C and the outer surface of the concrete wall is at 20°C.The thermal conductivities of concrete and wood are 0.80 W/m ∙ K (concrete) and 0.040 W/m ∙ K (wood) .What is the temperature difference across the layer of wood?
A) 24°C
B) 25°C
C) 26°C
D) 27°C
E) 28°C
Correct Answer:

Verified
Correct Answer:
Verified
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