Question

Why soft iron core is placed inside solenoid ?

Answer 1

by placing an iron core inside the solenoid the strength of the magnetic field increases.

Answer 2

It has been found that if a soft iron rod called core is placed inside a solenoid, then the strength of the magnetic field becomes very large because the ironore is magnetized by induction. ... Thus, an electromagnet consists of a long coil of insulated copper wire wound on a soft iron core.

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