  We studied the dynamical phase transition in kinetic Ising ferromagnets
driven by oscillating magnetic field in meanfield approximation. The meanfield
differential equation was solved by sixth order Runge-Kutta-Felberg method. The
time averaged magnetisation plays the role of the dynamic order parameter. We
studied the relaxation behaviour of the dynamic order parameter close to the
transition temperature, which depends on the amplitude of the applied magnetic
field. We observed the critical slowing down along the dynamic phase boundary.
We proposed a power law divergence of the relaxation time and estimated the
exponent. We also found its dependence on the field amplitude and compared the
result with the exact value in limiting case.
