A uniform straight cylindrical wire has length L and radius a. An electric potential difference V is maintained between the two ends of the wire such that a constant current I flows down it. (a) Find the magnitude and direction (according to the direction of current flow) of electric and magnetic field by the surface of the wire. (b) Compute the magnitude and direction of the Poynting vector by the surface of the wire. (c) Integrate the Poynting vector over the surface of the wire to find the total flow of energy/power. (d) What happens to the energy? Interpret your results.

A uniform straight cylindrical wire has length L and radius a. An electric potential difference V is maintained between the two ends of the wire such that a constant current I flows down it. (a) Find the magnitude and direction (according to the direction of current flow) of electric and magnetic field by the surface of the wire. (b) Compute the magnitude and direction of the Poynting vector by the surface of the wire. (c) Integrate the Poynting vector over the surface of the wire to find the total flow of energy/power. (d) What happens to the energy? Interpret your results.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter16: Electromagnetic Waves

Section: Chapter Questions

Problem 99AP: The Poynting vector describes a flow of energy whenever electric and magnetic fields are present....

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