A) (2 marks) An exterior wall of a house with (12 cm )thickness of common brick (k-0.7W/m.'C) followed by 4cm of plaster (k-0.5 W/m. C), the temperature difference between the outer surface and the inner surface is equal to (20° C) calculate: 1)The heat loss through the wall per unit area. 2) In order to reduce the heat flow to one half (50%) an additional layer must be added to the wall with (2cm) thickness. find the thermal conductivity of this layer, maintaining the temperature at the same level.

A) (2 marks) An exterior wall of a house with (12 cm )thickness of common brick (k-0.7W/m.'C) followed by 4cm of plaster (k-0.5 W/m. C), the temperature difference between the outer surface and the inner surface is equal to (20° C) calculate: 1)The heat loss through the wall per unit area. 2) In order to reduce the heat flow to one half (50%) an additional layer must be added to the wall with (2cm) thickness. find the thermal conductivity of this layer, maintaining the temperature at the same level.

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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