How do the relative permeabilities of paramagnetic materials behave________________?
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Answer: C. slightly more than unity
Explanation
Paramagnetic materials have relative permeabilities that are very close to, but slightly greater than, unity. This slight positive magnetic susceptibility causes them to be weakly attracted to external magnetic fields. Their atomic dipoles tend to align weakly with applied fields, enhancing the overall flux slightly. Paramagnetism occurs in materials with unpaired electrons whose thermal energy randomizes alignment. Unlike ferromagnets, paramagnetic materials retain no residual magnetism when external fields are removed. Aluminum, platinum, and oxygen are well-known examples of weakly paramagnetic substances.
Paramagnetic properties are often studied in low-temperature physics to observe quantum alignment effects. Oxygen gas sensors utilize paramagnetic principles to measure oxygen concentrations in industrial flue gases. Engineering applications rarely utilize paramagnetism because the magnetic response is extremely weak. Relative permeabilities slightly less than unity characterize diamagnetic materials, not paramagnetic ones. Relative permeabilities equal to unity describe free space or vacuum conditions without matter. Permeabilities equal to ferromagnetic materials are vastly higher than those of paramagnetic substances.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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