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Question
A wire carries an alternating current i = i0 sin ωt. Is there an electric field in the vicinity of the wire?
Solution
When an alternating current passes through a conductor, the changing magnetic field create a changing electric field outside it. An electromagnetic field is radiated from the surface of the conductor. There is a time-varying electric field outside the conductor. Hence, there is a time-varying electric field in the vicinity of the wire.
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