a) A house walls that are 17 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 1600000 cm2 and their inside surface is at 21° C, while their outside surface is at 5°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 17 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 1600000 cm2 and their inside surface is at 21° C, while their outside surface is at 5°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)

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 97P: Compare the rate of heat conduction through a 13.0-cm-thick wall that has an area of 10.0 m2 and a...

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Check Your Understanding How does the rate of heat transfer by conduction change when all spatial dimensions are doubled?