Magnetic forces like those caused by Earth’s geomagnetic field may seem mysterious. These forces act on objects at a distance, and we can’t see or touch them. To help visualize magnetic forces, scientists model them using magnetic field lines. These scientific models help scientists predict and explain how magnetic forces work. In a model of a single magnet, lines are drawn looping outward between opposite magnetic poles.
In a model with more than one magnet, the field lines are sometimes drawn connecting opposite poles on the magnets. These field lines help predict the direction of the forces pulling or pushing different magnets. A model showing field lines connecting the opposite poles of different magnets indicates that the magnets will be attracted together. A model showing two magnets that are not connected to each other by field lines indicates that the magnets will repel each other.