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प्रश्न
Soft iron is used to make the core of the transformer because of its ______.
विकल्प
Low coercivity and low retentivity
Low coercivity and high retentivity
High coercivity and high retentivity
High coercivity and low retentivity
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उत्तर
Soft iron is used to make the core of the transformer because of its Low coercivity and low retentivity.
Explanation:
Soft iron is used to make the core of transformers because of its high permeability. This enables complete magnetic flux coupling from the main coil to the secondary coil, and it possesses low retentivity and low coercivity.
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Assertion: Electromagnetic are made of soft iron.
Reason: Coercivity of soft iron is small.
