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प्रश्न
What should be retentivity and coercivity of permanent magnet?
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उत्तर
A permanent magnet should have a high zero-field magnetization and require a high reverse field to demagnetize. In other words, it should have a wide hysteresis loop with high retentivity and coercivity.
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संबंधित प्रश्न
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Answer in brief.
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