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The wall of a refrigerator is costructed of fiberglass insulation sandwiched between two layers of sheet metal.The minimum thickness of insulation that needs to be used in the wall in order to avoid condensation on the outer surface to be determined.
Thermal conductivity for sheet metal = 15.5 W/m deg C
Thermal conductivity for fiberglass insulation = 0.035 W/m deg C
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