Two magnetic field lines produced by the same source

A fundamental property of magnetic field lines is that they never intersect each other [1]. This is because the tangent to a field line at any given point represents the direction of the net magnetic field at that specific location. If two field lines were to cross, it would imply that at the point of intersection, the magnetic field has two different directions simultaneously [1]. This is physically impossible as a compass needle placed at that point cannot point in two directions at once [1]. Furthermore, magnetic field lines form continuous closed loops, moving from the north pole to the south pole outside the magnet and from south to north inside [1]. This continuity and the uniqueness of the field direction at every point ensure that lines produced by the same source (or even different sources) never cross [1].

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 12: Magnetic Effects of Electric Current > Activity 12.3 > p. 197