Electromagnets are made up of soft iron because soft iron has
Correct answer: C. Low retentivity and low coercive force
- A. Low retentivity and high coercive force
- B. High retentivity and high coercive force
- C. Low retentivity and low coercive force
- D. High retentivity and low coercive forces
Explanation
Electromagnets are made of soft iron because it has low retentivity and low coercive force, meaning it can be easily magnetised and demagnetised. This property is crucial for electromagnets, which need to turn on and off easily. Soft iron quickly loses its magnetism when the electric current is removed, making it ideal for this purpose. Option A is incorrect because high coercive force would make the material difficult to demagnetise. Option B is unsuitable due to both high retentivity and high coercive force, characteristics of permanent magnets. Option D is incorrect because high retentivity means the material would not lose its magnetism easily, which is not desired for electromagnets.
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