Which material is best for making a permanent magnet?

Step 1: Analyze the question We need a material that makes a permanent magnet, meaning one that keeps its magnetism for a long time after being magnetized.

Step 2: The concept A permanent magnet needs a material with:

• High retentivity: it keeps its magnetism after the magnetizing field is removed.
• High coercivity: it resists being demagnetized.

Such materials are called hard magnetic materials. Steel is the classic example (and alloys like Alnico). Soft magnetic materials such as soft iron magnetize easily but lose their magnetism just as easily. That makes them good for temporary magnets like electromagnets, transformer cores, and relay cores.

Step 3: Check each option

• A. Aluminium: paramagnetic, very weakly attracted to magnets, and cannot be made into a permanent magnet.
• B. Cobalt: it is ferromagnetic and is used in some magnet alloys. But pure cobalt is not the standard answer for a simple permanent magnet. Steel is the usual textbook choice.
• C. Copper: diamagnetic, so it is not magnetic at all.
• D. Soft iron: it magnetizes strongly but loses its magnetism quickly, so it suits temporary magnets.
• E. Steel: it is harder to magnetize, but once magnetized it retains its magnetism well. This makes it best for permanent magnets.

Step 4: Answer The correct option is **E.

Exam tip: Remember "Steel = Stays, Soft iron = Switches off." Steel keeps its magnetism (permanent magnets), while soft iron loses it (electromagnets and cores). Questions on this topic appear often in NECO, WASSCE, and JAMB.