Question

Why the strength of electromagnet increases when the soft iron core is laminated

Answer 1

Dear student,
The soft iron inside the coil makes the magnetic field stronger because it becomes a magnet itself when the current is flowing. Soft iron is used because it loses its magnetism as soon as the current stops flowing.
Iron core is thin & laminated to avoid the loss of eddy current. Eddy current is induced in core and circulates normal to the width of the core causing heat.
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