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 thermal energy 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°


D

Physics & Space Science

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When a switch is closed, completing an LR series circuit, the time needed for the current to reach three-quarters its maximum value is ____ time constants

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The work done by the gas is zero during an

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Physics & Space Science