where c is
called Curie constant. It is therefore evident from equation (14) that the
magnetic susceptibility for a paramagnetic substance is inversely proportional
to the absolute temperature.
Q.6 What is hysteresis curve? Explain residual
magnetism and coercive force. Prove that the energy dissipated per cc. of
magnetization is m0 times the area of I – H curve. (AKTU. 2002 - 03)
Related
Questions -
Q. What is hysteresis curve? Explain
residual magnetism and coercive force. (AKTU. 2005 - 06, 09-10)
Q. What is hysteresis curve? (AKTU. 2010 - 11)
Ans. Hysteresis loss: -
When a magnetic material is placed
in a magnetic field, there is a loss of energy because energy is required in
aligning the molecular magnets in the direction of applied magnetic field. This
energy waste in the work, which is done by magnetic field against the mutual
attractive force acting among them. This loss of energy is called hysteresis
loss.
Hysteresis
Curve: -
Let us consider there is a
ferromagnetic material, which is placed in an external magnetic field H. The
intensity of magnetization (I) and hence the flux density (B) increases with
increase of external field (H), this is shown by OA curve. At point A condition
of saturation occurs.
