MCQ
Pick out the material that cannot be used to make permanent magnets.
- ACopper
- BAluminum
- CSteel
- DZinc
✓
Answer
- Zinc
Explanation:
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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