Why are field lines never crossing in diagrams?

Field lines never cross in diagrams because each point in space can only have one direction of the field at a time.

In more detail, field lines are a visual tool used in physics to represent vector fields. They are used to illustrate the direction and strength of a field, such as an electric field or a magnetic field. The direction of the field at a particular point in space is represented by the direction of the field line at that point, while the strength of the field is represented by the density of the field lines.

If field lines were to cross, it would imply that the field has more than one direction at that point, which is not possible. A field can only have one direction at a given point in space. Therefore, field lines are drawn so that they never cross.

Moreover, the concept of field lines is based on the principle that they always move from high potential to low potential in the case of electric fields, and from North to South in the case of magnetic fields. If field lines were to cross, it would create confusion about the direction of the field.

In addition, the density of field lines is used to represent the strength of the field. If field lines were to cross, it would artificially inflate the perceived strength of the field at the point of intersection, which would be misleading.

In conclusion, field lines are drawn so that they never cross to accurately represent the direction and strength of the field at each point in space. This is a fundamental principle in the study of fields in physics, and is crucial for understanding the behaviour of fields.