(3) Determine the permissible value of electrical current flowing copper wire of d=2 mm diameter, covered with rubber insulation with a thickness of 8=1 mm, if it is known that the temperature of the insulation can not be larger than 333 K. The calculations assume: electrical resistance of copper wire R=5-103 Q/m, conductivity of the rubber 2=0,15 W/(m-K), of surroundings heat transfer coefficient a,=8 W/(m²-K), at an ambient temperature of air t,=20°C.

(3) Determine the permissible value of electrical current flowing copper wire of d=2 mm diameter, covered with rubber insulation with a thickness of 8=1 mm, if it is known that the temperature of the insulation can not be larger than 333 K. The calculations assume: electrical resistance of copper wire R=5-103 Q/m, conductivity of the rubber 2=0,15 W/(m-K), of surroundings heat transfer coefficient a,=8 W/(m²-K), at an ambient temperature of air t,=20°C.

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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