a) A house walls that are 20 cm thick and have an average thermal conductivity four times that of glass wool. Assume there are no windows or doors. The walls' surface area is 1000000 cm² and their inside surface is at 23° Çwhile their outside surface is at 4°C (Thermal conductivity of glass wool is 0.042 W/m°C) (i) Calculate the rate of heat conduction through house walls? (ii) How many 150W room heaters would be needed to balance the heat transfer due to conduction? (approximate number)

a) A house walls that are 20 cm thick and have an average thermal conductivity four times that of glass wool. Assume there are no windows or doors. The walls' surface area is 1000000 cm² and their inside surface is at 23° Çwhile their outside surface is at 4°C (Thermal conductivity of glass wool is 0.042 W/m°C) (i) Calculate the rate of heat conduction through house walls? (ii) How many 150W room heaters would be needed to balance the heat transfer due to conduction? (approximate number)

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter20: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 20.78AP

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