Multiple Choice

A long straight wire of radius R carries a current distributed uniformly over its cross-section. The magnitude of the magnetic field is

Amaximum at the axis of the wire
Bminimum at the axis of the wire
Correct Answer
Cmaximum at the surface of the wire
Correct Answer
Dminimum at the surface of the wire

Solution

For a current carrying long straight wire, if the current distributed uniformly over its cross-section then the magnitude of the magnetic field is minimum at the axis of the wire maximum at the surface of the wire.

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