A 2.2-mm-diameter and 10-m-long electric wire istightly wrapped with a 1-mm-thick plastic cover whose thermalconductivity is K = 0.15 W/m·K. Electrical measurementsindicate that a current of 13 A passes through the wire and there is a voltage drop of 8 V along the wire. If the insulatedwire is exposed to a medium at T` = 30°C with a heat transfercoefficient of h = 24 W/m2·K, determine the temperature at theinterface of the wire and the plastic cover in steady operation.Also determine if doubling the thickness of the plastic coverwill increase or decrease this interface temperature.

A 2.2-mm-diameter and 10-m-long electric wire istightly wrapped with a 1-mm-thick plastic cover whose thermalconductivity is K = 0.15 W/m·K. Electrical measurementsindicate that a current of 13 A passes through the wire and there is a voltage drop of 8 V along the wire. If the insulatedwire is exposed to a medium at T` = 30°C with a heat transfercoefficient of h = 24 W/m2·K, determine the temperature at theinterface of the wire and the plastic cover in steady operation.Also determine if doubling the thickness of the plastic coverwill increase or decrease this interface temperature.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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