Mention any four characteristics of a magnetic field line.

The lines representing the magnetic field are called magnetic field lines. The magnetic field lines have the following characteristics:

1. Magnetic field lines never intersect with each other. 

2. They form a closed loop. 

3. The field lines have both direction and magnitude at any point on the field. 

4. The relative strength of the magnetic field is shown by the degree of closeness of the field lines.