An infinitely long thin wire carrying a uniform linear static charge density λ is placed along the z-axis (Fig. 8.1). The wire is set into motion along its length with a uniform velocity . Calculate the poynting vector .



The electric field produced by the infinitely long thin wire is given by,



The magnetic field produced by the infinitely long thin wire is given by,



The current flowing through the wire is, I = λ×v


Hence,



Poynting vector is given by,





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