Hysteresis, Soft Iron vs Steel & Shielding
Hysteresis loops for two magnetic materials and are given below:
These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use:
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Answer: (b)
- Loop A is wide, so it has high retentivity and high coercivity. This suits permanent magnets, such as those in electric generators.
- Loop B is narrow, so it has low coercivity, small hysteresis loss and is easily demagnetised. This suits transformer cores and electromagnets.
- So the answer is (b): B for electromagnets and transformers.