Question

A soft iron piece is in the form of a closed ring (no free ends). A wire is wound over it to make it an electromagnet. What happens when current is passed in the wire ?
(a) It does not get magnetised.
(b) It gets temporarily magnetised.
(c) It becomes magnetised.
(d) It can be magnetised if broken into two parts.

April 3, 2024

Answer

(c) It becomes magnetised

Reason — When the current flows through the soft iron piece in the form of a closed ring, it becomes magnetised. The north and south poles will be present on opposite sides of the ring.

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