Scaling behaviour of the maximal growth rate in the Rosensweig instability

The dependence of the maximal growth rate of the modes of the Rosensweig in stability on the properties of the magnetic fluid and the external magnetic induction is studied. An expansion and fit procedure are applied in the ap propriate ranges of the supercritical induction (B) over cap. With increasi ng (B) over cap the scaling of the maximal growth rate changes from linear to combination of linear nd square-root like scaling. The scaling of the co rresponding wave number alternates from quadratic to primarily linear. For very small (B) over cap the dependence of the maximal growth rate on the vi scosity is given. Suggestions are made for experiments to test the predicte d scaling behaviours.