
These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use:

for transformers and
for electric generators.
As we know that, area of Hysteresis loop represents the net loss of energy by the material per unit volume,taken over complete cycle.

Graph is hard ferromagnetic material substance as the area of the loop is more, hence the hysteresis loss will be more and thus the value of coercivity will be high which are best suited to use as Permanent Magnet
Graph is graph of soft ferromagnetic material substance as the area of the loop is less and hence the hysterisis loss will be less which is required condition for transformer. And the value of coercivity will be low too.
Hence this material are best suited to use as Electromagnets and Transformer.
Asked in: JEE Main 2016 (03 Apr)
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