In a normal conductor heat is generated at a rate I 2R. Therefore a current-carrying conductor must dissipate heat effectively or it can melt or overheat the device in which it is used. Consider a long cylindrical copper wire (resistivity 1.72x 10-8 Ω*m) of diameter 0.75 mm. If the wire can dissipate 80 W/m2 along its surface, what is the maximum current this wire can carry?

In a normal conductor heat is generated at a rate I 2R. Therefore a current-carrying conductor must dissipate heat effectively or it can melt or overheat the device in which it is used. Consider a long cylindrical copper wire (resistivity 1.72x 10-8 Ω*m) of diameter 0.75 mm. If the wire can dissipate 80 W/m2 along its surface, what is the maximum current this wire can carry?

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter12: The Solid State

Section: Chapter Questions

Problem 12P

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