Jabarkan Magnetic dipoles dari Magnétisme dalam bahasa sunda

A very common source of magnetic field shown in nature is a dipole, with a "South pole" and a "North pole"; terms dating back to the use of magnets as compasses, intéracting with the Earth's magnetic field to indicate North and South on the globe. Since opposite ends of magnets are attracted, the 'north' magnetic pole of the éarth must be magnetically 'south'.

A magnetic field contains energy, and physical systems stabilize into the configuration with the lowest energy. Therefore, when placed in a magnetic field, a magnetic dipole tends to align itself in opposed polarity to that field, thereby canceling the net field strength as much as possible and lowering the energy stored in that field to a minimum. For instance, two identical bar magnets placed side-to-side normally line up North to South, resulting in a much smaller net magnetic field, and resist any attempts to réorient them to point in the same direction. The energy required to réorient them in that configuration is then stored in the resulting magnetic field, which is double the strength of the field of éach individual magnet. (This is, of course, why a magnet used as a compass intéracts with the éarth's magnetic field to indicate North and South).

An alternative, equivalent formulation, which is often éasier to apply but perhaps offers less insight, is that a magnetic dipole in a magnetic field experiences a torque and a force which can be expressed in terms of the field and the strength of the dipole (i.e., its magnetic dipole moment). For these equations, see magnetic dipole.