Q 12-05-022NEETJEE MainEasy
Materials used for making permanent magnets should have
Answer: (A) high retentivity and high coercivity
A permanent magnet must keep its magnetisation (high retentivity) and resist being demagnetised (high coercivity), e.g. steel or alnico. Electromagnet cores and transformer cores need the opposite: low coercivity and small hysteresis loss.
Solution by Sreeraj P, M.Sc Physics