By what means can the inductance of a coil be successfully increased_________?
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Answer: D. choosing core material having high relative permeability
Explanation
Relative permeability measures a core material ability to concentrate magnetic flux lines effectively. Higher permeability allows more magnetic flux to be established per unit of current. Since inductance depends directly on magnetic flux linkage, high permeability increases inductance. Inductance is proportional to the square of the number of coil turns. Increasing core length actually decreases coil inductance by spreading magnetic flux out. Larger former diameters increase inductance by expanding the cross sectional area available.
Transformer and inductor manufacturers use ferromagnetic cores to achieve high inductance values compactly. Selecting appropriate core materials prevents magnetic saturation in high frequency electronic devices. Electromagnets rely on high permeability iron cores to maximize lifting force capabilities. Increasing core length reduces inductance because magnetic reluctance becomes significantly greater. Decreasing the number of turns lowers inductance since flux linkage drops proportionally. Decreasing the diameter of the former reduces the cross sectional area lowering inductance.
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- Engineering
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- Electrical Engineering
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- —
- Difficulty
- medium
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