Question
Answer the following question:
‘A system displaying a hysteresis loop such as a ferromagnet, is a device for storing memory?’ Explain the meaning of this statement.
Solution
Magnetisation of a ferromagnet is not a single-valued function of the magnetising field. Its magnetisation value for a particular field depends both on the field and also on history of magnetisation (i.e., how many cycles of magnetisation it has gone through etc.).
In other words, the value of magnetisation is a record or ‘memory’ of its cycles of magnetisation. If information bits can be made to correspond to these cycles, the system displaying such a hysteresis loop can act as a device for storing information.
