A Magnetic field is generally interpreted as a region where the force of magnetism acts. This force of magnetism is mainly produced as a result of a moving charges or some magnetic material.
Form finely long straight current-carrying conductor magnetic field; B = MoI/4πa
= B ∝ 1/a
Magnetic field intensity is inversely proportional to the distance from the conductor.
Therefore, the explanation is inversely proportional to the distance from the conductor.
Note:
Characteristics of the magnetic field due to a current-carrying conductor
- It encircles the conductor.
- It lies in a plane perpendicular to the conductor.
- The reversal in direction of current flow reverses the direction of the field.
- The strength of the field is directly proportional to the magnitude of the current.
- The strength of the field is inversely proportional to the distance of the point from the wire.