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4. The wall of a house is 3 m high and 6 m wide, made of...

4. The wall of a house is 3 m high and 6 m wide, made of plywood (k = 0.11 J/(s•m•C°) 1.9 cm thick. The

inside of the house is maintained at 72°F (22°C) by an air conditioning unit, while the outside is 88°F (31°C) in the middle of the day.

  1. A) What is the thermal resistance of the wall?

  2. B) How much heat passes through the wall in one hour?

The wall is covered with a layer of fiberglass insulation (k = 0.04 J/(s•m•C°) 10 cm thick. C) What is the new thermal resistance of the wall?

D) How much heat passes through the insulated wall in one hour?

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Answer #1

Note after insulation the heat flow is decreased by order of 10

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