Q3. A small electric heating application uses wire of 2 mm diameter with 0.8 mm thick insulation (k = 0.15 W/m°C). The heat transfer coefficient (ho) on the insulated %3D surface is 31 W/m2°C. Determine the critical thickness of insulation in this case and the percentage change in the heat transfer rate if the critical thickness is used, assuming the temperature difference between the surfaces of the wire and surrounding air remains unchanged. Wire Insulator ho k 0.8 mm

Q3. A small electric heating application uses wire of 2 mm diameter with 0.8 mm thick insulation (k = 0.15 W/m°C). The heat transfer coefficient (ho) on the insulated %3D surface is 31 W/m2°C. Determine the critical thickness of insulation in this case and the percentage change in the heat transfer rate if the critical thickness is used, assuming the temperature difference between the surfaces of the wire and surrounding air remains unchanged. Wire Insulator ho k 0.8 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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