Consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 W/m-°C) with 1.5-mm-thick air space (k = 0.026 W/m- °C) between the layers. Assuming the inner surface temperature of the jacket to be 28°C and the surface area to be 1.1 m2, the temperature of the outdoors is -5°C and the heat transfer coefficient at the outer surface is 25 W/m2-°C. What should be the thickness of a wool fabric (k = 0.035 W/m-°C) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket? mm

Consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 W/m-°C) with 1.5-mm-thick air space (k = 0.026 W/m- °C) between the layers. Assuming the inner surface temperature of the jacket to be 28°C and the surface area to be 1.1 m2, the temperature of the outdoors is -5°C and the heat transfer coefficient at the outer surface is 25 W/m2-°C. What should be the thickness of a wool fabric (k = 0.035 W/m-°C) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket? mm

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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