Magnetism is a flux or field of unknown origin (aether)
The strength of this field decreases with the square of the distance from its origin. Different degrees of field strength are recorded depending on the properties of the different natural elements, or the combination of different elements composing a magnet.
Magnets of natural origin are called lodestones. Lodestones are, for the most part, composed of iron ore and are found naturally magnetized. When a piece of iron is exposed to an intense polarized magnetic field, the iron becomes "magnetized." The iron retains some of the magnetic properties of the source of energy and becomes a permanent magnet with the "north and south" pole characteristics. A permanent magnet remains magnetized for an unknown duration if it is kept undisturbed by electrical, magnetic, thermal or mechanical action.
The field emanating from the magnet can be compared to the water coming out of a garden hose on which the nozzle is opened and from that point dispenses water for eternity. Note: by rotating the hose the water does not rotate. Just as the water does not "belong" to the hose, the magnetic field does not "belong" to the magnet.
When a permanent magnet is displaced rapidly and perpendicularly in close proximity to a conductive element, like a copper wire, an electrical current is generated and circulates in the wire (Right hand rule). Technically speaking, the field of the magnet "induces" an electrical current in the conductor. The faster the magnet is moved, the stronger the induced current. Without motion, no current is generated. A conductor can be anything conductive, elements such as many metals or even a saline solutions (salt water). The sap of plants, blood of animals or humans are all saline solutions and therefore electrical conductors. Blood vessels can be in effect, the "wire" in which the current is generated and propagates.
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