Understand: electric and magnetic fields

A horizontally oriented rectangle represents a magnet. Extending from many points all around the magnet are curved lines that represent a magnetic field. The lines form concentric loops that come out and back into the magnet. The loops are smallest above and below the middle of the magnet and grow larger as you go toward each end. The lines spread out with with increasing distance from the magnet. Four areas are labeled. Areas A and D are relatively far from the magnet. In these areas, the lines are very spread out. Area B is above the center of the magnet, where the lines are closer together than in areas A and D. Area C is closest to the magnet and near one end of the magnet. Here, lines are closer together than in the other labeled areas.