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प्रश्न
A magnetic field can be produced by
पर्याय
a moving charge
a changing electric field
Neither of them
Both of them
उत्तर
Both of them
According to Ampere-Maxwell's Law, a magnetic field is produced due to the conduction current in a conductor and the displacement current. The conduction current is actually the motion of the charge. The displacement current is due to the changing electric field. The displacement current is given by `i_d = ∈_0 (dΦ_E)/dt` (∵ `Φ_E` is the electric flux).
Thus, the magnetic field is produced by the moving charge as well as the changing electric field.
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