= Consider a long resistance wire of radius r₁ = 0.3 cm and thermal conductivity kwire 18 W/m. °C in which heat is generated uniformly at a constant rate of g = 1.5 W/cm³ as a result of resistance heating. The wire is embedded in a 0.4-cm- thick layer of plastic whose thermal conductivity is kplastic = 1.8 W/m. °C. The outer surface of the plastic cover loses heat by convection to the ambient air at T = 25°C with an average combined heat transfer coefficient of h = 14 W/m². °C. As- suming one-dimensional heat transfer, determine the tempera- tures at the center of the resistance wire and the wire-plastic layer interface under steady conditions. Answers: 97.1°C, 97.3°C

= Consider a long resistance wire of radius r₁ = 0.3 cm and thermal conductivity kwire 18 W/m. °C in which heat is generated uniformly at a constant rate of g = 1.5 W/cm³ as a result of resistance heating. The wire is embedded in a 0.4-cm- thick layer of plastic whose thermal conductivity is kplastic = 1.8 W/m. °C. The outer surface of the plastic cover loses heat by convection to the ambient air at T = 25°C with an average combined heat transfer coefficient of h = 14 W/m². °C. As- suming one-dimensional heat transfer, determine the tempera- tures at the center of the resistance wire and the wire-plastic layer interface under steady conditions. Answers: 97.1°C, 97.3°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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Question

Consider a long resistance wire of radius r₁ = 0.3 cm
and thermal conductivity kwire = 18 W/m. °C in which heat is
generated uniformly at a constant rate of g = 1.5 W/cm³ as a
result of resistance heating. The wire is embedded in a 0.4-cm-
thick layer of plastic whose thermal conductivity is kplastic = 1.8
W/m. °C. The outer surface of the plastic cover loses heat by
convection to the ambient air at T = 25°C with an average
combined heat transfer coefficient of h = 14 W/m². °C. As-
suming one-dimensional heat transfer, determine the tempera-
tures at the center of the resistance wire and the wire-plastic
layer interface under steady conditions.
Answers: 97.1°C, 97.3°C
T
Wire
·00
h
Plastic cover

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