Why cant magnetic field lines cross?
Rey M's answer is excellent. I don't claim that mine is better, but here's an alternative way to say the same thing. A magnetic field line is the path an isolated N or S monopole would follow if allowed to do its thing unhindered. More realistically, since nobody has ever found a monopole, it's the direction a compass needle would point if placed there, hence the high school experiment of placing a magnet underneath a piece of card and scattering iron filings on the card. A monopole can't move in two directions at once, and a compass needle can't point in two directions at once. So you can't have two field lines crossing.
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It's true that the lines only show magnetic fields. But it is possible to cross magnetic fields getting both attraction and repulsion . This was tested using many magnets forcing the fields to cross wich will pull another magnet in but only to a certain point. Keeping it at a set distance. Up dates coming soon look for my book coming soon to Amazon
here is the answer Magnetic field lines are just a representation of the field itself. The lines are not real in that sense, but they tell us where the field is pointing at any chosen point in space. Now if the lines cross, that would mean that the field at the crossing point is pointing in two directions which would be contradicting our original idea. A horse shoe magnet is made of hard magnetic material where the magnetisation is stiff and less flexible than in a soft iron magnet. Hence we do not use a horseshoe magnet for electromagnets because we cannot control the magnetisation as well as we can for the soft iron. However, you can still use electromagnetic methods to magnetise the horseshoe magnet. Nobody knows how earth's field comes about. here is my other answer Field lines don't cross because a magnetic object placed at a point in the field moves only in 1 direction due to attraction or repulsion. If 2 lines crossed, it means the object can move in 2 directions, which is not the case!
