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प्रश्न
Which property of soft iron makes it useful for preparing electromagnet?
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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संबंधित प्रश्न
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(a) P1 and P2
(b) Q1 and Q2
(c) P1 and Q1
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(b) a deflection galvanometer if the earth's horizontal field is known
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(d) both deflection and oscillation magnetometer if the earth's horizontal field is not known
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In a permanent magnet at room temperature ______.
Assertion: Electromagnetic are made of soft iron.
Reason: Coercivity of soft iron is small.
