Physics

How Electrical Current Flows



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In his work, 'A Treatise on Electricity and Magnetism', James Maxwell wrote: Faraday, in his mind's eye, saw lines of force traversing all of space, where the mathematicians saw centers of force attracting at a distance. Faraday saw a medium where they saw nothing but distance. Faraday sought the seat of the phenomenon in real actions going on in a medium, while they were satisfied that they had found it in a power of action at a distance impressed on the electric fluids. (The model of fluids, pressures, and vacuums was very popular at this time.)

With the exception of lightening, the discovery of static electricity was our first experience with electric current. An electrostatic field (static electricity) is composed of individual electrons behaving as a collective. While repelling one another, electrons collectively radiate a larger electric field. The larger field expresses characteristics similar to those shown by the single electron. It is attracted to positively charged fields, and repels negative fields.

Electrons are attracted to protons, in the same way they are attracted to positrons. Unlike positrons, protons have a true magnetic field, with north and south poles, and a gravity field. The gravity field has no effect on electrons, but the magnetic field has Van Allen belts (similar to those surrounding the Earth and the Sun) which act as barriers, blocking electrons from joining with the positron energy of the proton. The Van Allen belts are normally referred to as electron shells or quantum paths in the standard model. (I use an alternative 'field' theory.) It is electrical attraction and magnetic repulsion which provides the foundation of electric current.

A static electric field normally forms as the result of atoms losing electrons from their outer orbits, and becoming ionized. In a clothes dryer, electrons are lost due to friction and thermal field expansion, with electrons collecting on the surface of the fabric.

An electrostatic field is loosely stationary until it interacts with ionized matter, or a conductor capable of transferring the electric field to matter with a shortage of electrons. The strength of an electrostatic field is partially dependent on the quantity of accumulated electrons and partially dependent on the strength of the proton attraction contained within the ionized matter. The larger the number of excess electrons, the stronger the field. When powerful enough, an electrostatic field can move through the air, or even through an insulator, to reach ionized matter. Lightning and static electric shocks are both examples of this process.

Standard convention teaches direct electric current flows from the positive to the negative. This "conventional" model was developed early in electrical research and was based on the assumption a positive force was filling a negative void. It was later discovered 'negatively' charged electrons, moving toward the 'positive pole', are responsible for electrical current. Correcting this model error within the education system has been remarkably difficult.

Though a growing number of text books describe our present understanding of electron movement, some texts continue to use the "conventional" current model. This is the result of a philosophy of convenience. Rather than changing several centuries of theory and contradicting older text books, this convention continues to be used in an effort to avoid paradigm confusion and lengthy discussions. Ease and conformity sometimes receive a higher priority than accurate information and its meanings. This process of avoiding updated information leads to unnecessary confusion.

Electrochemical cells (batteries) provide a convenient, portable form of energy, normally in the form of direct current. Static electricity was discovered and experimented with prior to developing electrochemical batteries. Direct current (DC) has a steady flow. Unlike alternating current, the charge flows in one direction only. Direct current is initiated when an excess of electrons move through a conductor seeking ions.

Electrochemical batteries are a traditional source of direct current. A non-rechargeable battery containing a zinc electrode and a copper electrode will provide direct current. Both metals are classified as electropositive, but zinc contains a large number of loose electrons, making the copper, comparatively speaking, electronegative, and attractive to loose and free electrons. Additionally, copper reacts much more slowly to acids than zinc. The two electrodes are separated by a solution of water and hydrochloric acid (a combination of hydrogen and chlorine).

Combining hydrochloric acid with a metal produces hydrogen gas. (Called single-replacement action.) The zinc's atoms have a stronger attraction to the chlorine atoms in the acid's molecules than do the weakly bonded hydrogen atoms. The chlorine atom's release the hydrogen cores ( a single proton) as they bond with the zinc atoms, but not the electrons. The chlorine atoms steal the hydrogen's weakly bound electrons, then carrying them to the zinc post. The zinc post builds an excess of loosely bound electrons, and creating a high pressure electric field.

The protons, released by single-replacement action, move through the acid toward the copper post and steal electrons from it, becoming hydrogen gas once again. The copper post now has a shortage of electrons. The basics for the production of direct electric current have been put in place. When a wire conductor is attached to the two posts, both electric fields react. The electric field, made up of loose electrons, are drawn toward the bound protons of the copper post, starting as an electromagnetic compression wave moving at the speed of light. After the initial EM wave passes through, the flow of electrons remains continuous for as long as there are excess electrons.

The protons within the copper post remain stationary, attracting any free electrons within the wire. With both posts connected by a conductor, the entire collective of free and loose electrons moves toward the copper post in a steady stream. As long as chemical reactions cause the zinc to gain electrons, and the copper to lose them, the current will continue. Typically, the zinc gradually dissolves into the electrolytic solution and the source of electrons disappears.

While electricity flows through the conductor it radiates a magnetic field with a circular north/south alignment, taking on equatorial characteristics. The unusual orientation of a magnetic field created during the passage of electric current provides a clue to the processes taking place inside the conductor. Per the East-West Geomagnetic effect, electrons flow to the east of a standard magnetic field expressing north and a south poles. In the case of electric current, the passing electrons reorient the magnetic fields of the atoms within the conductor. A compass placed in various positions around a wire conducting electricity finds no poles, but rather a circular magnetic field encompassing the wire, similar to the east and west directions running parallel to the Earth's equator. The compass will reverse itself when the direction of the current reverses.

During their movement, electrons seek out, or create, the path of least resistance. As part of this process, the magnetic orientation of the conductor's atoms are altered. The path of least resistance is through the magnetic equators, so the atoms' magnetic fields realign themselves, with neither the north nor south poles facing the oncoming electron flow. Their poles move to form a north/south relationship with the "astern" flow of electrons. As north and south poles attract one another, and like poles repel, the magnetic fields of atoms become aligned in ring shapes and radiate circular magnetic fields. As the magnetic fields shift, free and loosely bound valence electrons move through the newly formed layers between the magnetic rings. It is between the magnetic rings the electrons preferentially flow. Moving electrons also press the magnetic field lines outward and away from the conductor.

In the case of alternating current (AC) a magnetic pole (for example, north) is rotated into position at one end of the conductor, causing loose electrons to shift from repulsion. As the magnet continues to rotate, the south pole moves to influence the conductor's electrons, reversing the direction of their flow and the orientation of the magnetic field. The compression wave initiated by the rotating magnetic pole is the same as with the initial flow of direct current, and travels at the speed of light.

During the realignment process, loose and free electrons shift, becoming a collective voltage. The strength or attraction of the total number of electrons and their combined attraction to protons dictate the voltage. Amperage is about the number of electrons flowing past a specific point. Resistance is the difficulty electrons have in flowing through a material. A material with many loose electrons will have less resistance than one with few loose electrons.

In alternating current, the path of least resistance for the shifting electrons becomes the surface of the conductor. The constant shifting creates incredible electromagnetic turmoil within the conductor. The thickness of a material can have an effect as well. A thick wire will have less resistance than a thin one, simply because it has more loose electrons and more room for travel.

It is now possible to watch the flow of electricity. In April of 2003, a "magnetic" scanning microscope was developed at Brown University. It can observe the flow of electricity and can be used for both educational purposes and detecting defects in the smallest and most complex integrated circuits. It operates at a resolution 1,000 times greater than any previous scanning microscopes. This scanner can locate previously undetectable defects and sets the stage for developing smaller integrated circuits. Images produced by the microscope may be viewed at- http://www.micromagnetics.com/.

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