In this paper, we studied phenomenologically and numerically the ferromagnetic phase
transition and dynamic responses of bulk ferromagnet. We used Landau free energy density
expansion and applied the calculus of variations to formulate the second order
ferromagnetic phase transition. Then these are combined with Landau-Lifshitz (LL)
equation of motion in the study of chaotic dynamics of the bulk ferromagnet. The results
are presented graphically by using several different applied fields and frequencies.