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Bismuth, antimony, copper, zinc, mercury, gold, silver. Have a relative permeability of less than one
Diamagnetic materials
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Certain areas on an atom that are aligned such that their electrons tend to spin in the same direction
Domains
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The process of combining metals and chemicals to produce electrical energy.
Electrochemistry
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The magnitude of the induced voltage depends on two factors:
The number of turns in a coil
How fast the conductor cuts across the magnetic lines or force, or flux
Faraday’s law of induced voltage
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Iron, steel, nickel, cobalt, alnico and peralloy. Nonmagnetic but have the ferromagnetic properties of iron. Made of ceramic material and have relative permeabilities that range from 50 to 200. commonly used in the coils for RF transformers.
Ferromagnetic materials
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The concentration of the magnetic lines of force depending on the length of the coil.
Field intensity
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A lagging behind. When magnetic flux lags behind the magnetizing force in an iron core
Hysteresis
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The group of magnetic field lines emitted outward from the north pole of a magnet
Magnetic flux
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The amount of magnetic flux per unit area of a section, perpendicular to the direction of flux
Magnetic flux density
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The process of moving a conductor through a magnetic field to produce a potential difference.
Magnetic induction
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The result of electrons spinning on their own axis around the nucleus
Magnetism
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The strength of a magnetic field in a coil of wire
Magnetomotive force (MMF)
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Aluminum, platinum, manganese, chromium. Have a relative permeability of slightly more than one
Paramagnetic materials
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When a light beam strikes the surface of a material, they release their energy and transfer it to the atomic electrons of the material.
Photoelectric effect
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By applying pressure to certain crystals or certain ceramics, electrons can be driven out of orbit in the direction of the force. When the pressure is released, the electrons return to their orbits.
Piezoelectric
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Opposition to the production of magnetic flux in a material
Reluctance
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Electrons removed from the atoms due to friction
Static electricity
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The placing of two electrodes in a vacuum and heating one electrode causing electrons to flow
Thermionic emission
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Application of heat to the junction of two dissimilar metals causing electrons to flow from one to the other
Thermoelectricity
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DESCRIBE the following materials as they relate to permeability, including an example and an approximate permeability ratio:
a. Ferromagnetic materials
b. Paramagnetic materials
c. Diamagnetic materials
Ferromagnetic Materials: Some of the ferromagnetic materials used are iron, steel, nickel, cobalt, and the commercial alloys, alnico and peralloy. Ferrites are nonmagnetic, but have the ferromagnetic properties of iron. Ferrites are made of ceramic material and have relative permeabilities that range from 50 to 200. They are commonly used in the coils for RF (radio frequency) transformers.
Paramagnetic Materials: These are materials such as aluminum, platinum, manganese, and chromium. These materials have a relative permeability of slightly more than one.
- Diamagnetic Materials: These are materials such as bismuth, antimony, copper, zinc, mercury, gold, and silver. These
- materials have a relative permeability of less than one.
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EXPLAIN the cause of hysteresis losses
Hysteresis is defined as “a lagging behind”. The magnetic flux in an iron core lags behind the magnetizing force. When current in a coil reverses direction thousands of times per second, hysteresis can cause considerable loss of energy.
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DESCRIBE Faraday’s Law of Induced Voltage, including factors used in calculation and the calculation.
The magnitude of the induced voltage depends on two factors: (1) the number of turns of a coil, and (2) how fast the conductor cuts across the magnetic lines of force or flux.
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The ability of a material to concentrate magnetic lines of flux.
Permeability
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The current times the number of turns of the coil is expressed in units called
Ampere Turns
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