MCQ
Core of electromagnets are made of ferromagnetic material which has:
- AHigh permeability and Low retentivity.
- BHigh permeability and High retentivity.
- CLow permeability and High retentivity.
- DLow permeability and Low retentivity.
✓
Answer
- High permeability and Low retentivity.
Explanation:
Electromagnetic cores should have:
- High permeability so that it supports the formation of a magnetic field within itself.
- Low retentivity so that the magetic field so that it gets demagnetized easily.
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