As a ferromagnetic material undergoes a hysteresis loop, its magnetic susceptibility

Step-by-step solution

The magnetic susceptibility is defined as the ratio of magnetization M to the magnetizing field intensity H , given by = M H . At the point of retentivity on the hysteresis loop, H = 0 while M 0 . This gives = M 0 . Thus, the susceptibility can be infinite. At the point of coercivity, M = 0 while H 0 . This gives = 0 H = 0 . Thus, the susceptibility can be zero. In the regions of the loop where M and H have opposite signs (such as the second and fourth quadrants), the ratio M H is negative, meaning Since varies con