MCQ
Pick out the material that cannot be used to make permanent magnets.
- ACopper
- BAluminum
- CSteel
- ✓Zinc
✓
Answer
Correct option: D.
Zinc
Permanent magnets are made up of materials having high retentivity, high coercivity, and high permeability such as steel. Other suitable materials for making permanent magnets are alnico $($an alloy of iron, aluminum, nickel, copper, and cobalt$),$ cobalt steel, and ticonal. That leaves zinc as the one that cannot be used to make permanent magnets.
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