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प्रश्न
Which property of soft iron makes it useful for preparing electromagnet?
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उत्तर
When a current is passed through an electromagnet's coil, it should become magnetic, but once the current is turned off, it should lose its magnetism. As a result, the ferromagnetic core (usually iron-based) used in an electromagnet should have high permeability and low retentivity, i.e. be magnetically'soft.'
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