Answer the following questions
a. Explain qualitatively on the basis of domain picture the irreversibility in the magnetisation curve of a ferromagnet.
b. The hysteresis loop of soft iron piece has a much smaller area than that of a carbon steel piece. If the material is to go through repeated cycles of magnetisation , which piece will dissipate greater heat energy ?
c. 'A system displaying a hysteresis loop such as a ferromagnet , is a device for storing memory ? ' Explain the meaning of this statement.
d. What kind of ferromagnetic material is used for coating magnetic tapes in a cassette player , or for building ' memory stores ' in a modern computer ?
e. A certain region of space is to be shielded from magnetic fields . Suggest a method.