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प्रश्न
Explain, why steel is used in preference to soft iron for making permanent magnets while soft iron is used in preference to steel for making electromagnets.
उत्तर
Steel is used in preference to soft iron for making permanent magnets because steel acts as a magnet, even on the removal of inducing magnet and also steel has very high retention. Soft iron is used in preference to steel for making permanent magnets because soft iron behaves like a magnet as long as there is an inducing magnet and also soft iron has very poor magnetic retention.
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