The outside temperature on a particular winter's day is 0°C. Consider two identical houses, each of external surface area 200 m² and internal temperature 20°C. The walls of the first are constructed of a single layer of brick, of thermal conductivity 1 W m and thickness 20 cm. What is the heat flux Q out of this house? What is its rate of heat loss in Watts? The walls of the second house are constructed of two layers of brick, each 10 cm thick, and a layer of insulation, also 10 cm thick. The insulation is made mostly out of air, thermal conductivity 0.01 W m-1 °C-1. What are the heat flux and the rate of heat loss from this house? How different would your answer be if you neglected the layers of brick in this calculation? -1 °C-1

The outside temperature on a particular winter's day is 0°C. Consider two identical houses, each of external surface area 200 m² and internal temperature 20°C. The walls of the first are constructed of a single layer of brick, of thermal conductivity 1 W m and thickness 20 cm. What is the heat flux Q out of this house? What is its rate of heat loss in Watts? The walls of the second house are constructed of two layers of brick, each 10 cm thick, and a layer of insulation, also 10 cm thick. The insulation is made mostly out of air, thermal conductivity 0.01 W m-1 °C-1. What are the heat flux and the rate of heat loss from this house? How different would your answer be if you neglected the layers of brick in this calculation? -1 °C-1

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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