Hysteresis loops for two magnetic materials A and B are given below: These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use:

Step-by-step solution

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 A 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 B 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 trans