Question

Write the shape of the magnetic field produced by a current carrying straight conductor. State the rule to find the direction of this field.

Answer 1

The magnetic field produced by a current-carrying straight conductor is in the shape of concentric circles. The circles are centered on the conductor, and their planes are perpendicular to the conductor.

The direction of the magnetic field can be found using the right-hand thumb rule (or Maxwell’s right-hand corkscrew rule):

Right-hand thumb rule: If you grasp the conductor with your right hand such that your thumb points in the direction of the conventional current flow, then the direction in which your fingers curl represents the direction of the magnetic field lines around the conductor.