What serves as the standard unit for retentivity____________?
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Answer: B. weber/sq. m
Explanation
Retentivity quantifies the residual magnetic flux density remaining in a ferromagnetic material after field removal. Magnetic flux density is fundamentally defined as magnetic flux per unit cross sectional surface area. Weavers per square meter mathematically equate directly to teslas, which serve as the standard flux density unit. Magnetic flux is measured in webers in honor of the renowned German physicist Wilhelm Eduard Weber. Square meters represent the standard International System unit for measuring two dimensional cross sectional surface areas. Residual magnetism remains trapped inside ferromagnetic materials due to permanent domain wall pinning effects.
High retentivity values are critically important when manufacturing permanent magnets for electric motors and sensors. Low retentivity is conversely desired in transformer cores to prevent unwanted permanent magnetization buildup. Engineers test core materials thoroughly to ensure their magnetic retentivity meets strict industrial performance standards. The weber alone measures total magnetic flux rather than the flux density per unit surface area. Ampere turns per meter measures the strength of the applied external magnetizing field intensity. Ampere turns represent the standard engineering unit for total magnetomotive force inside an inductive coil.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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