Which substance is most frequently utilized for magnetic shielding or screening____________?
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Answer: C. soft iron
Explanation
Soft iron has very high magnetic permeability, allowing it to easily channel magnetic field lines. Magnetic lines naturally follow the path of least reluctance provided by the soft iron shield. This protective channeling effect diverts stray magnetic fields away from sensitive internal shielded spaces. Magnetic shielding protects sensitive instruments from external magnetic fields using high permeability enclosures. Soft iron contains minimal carbon impurities, maximizing its magnetic permeability and domain mobility. Reluctance in soft iron is extremely low compared to surrounding air, concentrating flux within the metal.
Cathode ray tube displays and sensitive laboratory scales rely on soft iron shielding for accuracy. Engineers enclose precision electrical measuring devices in soft iron boxes to prevent environmental interference. Proper shield thickness ensures the material does not saturate when exposed to strong external fields. Copper is a non-magnetic metal that relies on eddy currents rather than permeability for shielding. Aluminium possesses low magnetic permeability and provides poor shielding against static magnetic fields. Brass is an alloy of copper and zinc that offers no significant magnetic shielding properties.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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