Q. 75.0( 2 Votes )
A steady electric current is flowing through a cylindrical conductor.
A. The electric field at the axis of the conductor is zero.
B. The magnetic field at the axis of the conductor is zero
C. The electric field in the vicinity of the conductor is zero
D. The magnetic field in the vicinity of the conductor is zero.
Using Ampere’s law, the electric field due to a current carrying conductor of cross section areas is:
dl is the current element,
μ0 is the permeability of free space,
i is the current flowing
R is the radius of the conductor.
At the axis,
R=0 and so no area to enclose current.
Hence, B=0 at the axis of the conductor.
Electric field in the vicinity of the conductor is zero as a minimum distance between the point and the conductor is required to have electric field at that point.
Thus, options (B) and (C) are correct options.
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