Experiments with Magnetic Fluid
A permanent magnet providing a vertical magnetic field is placed under a container with magnetic fluid. In fig 1 the distance is still a few cm so that the field is just abot 100kA/m at the surface of the fluid.
In this case the Rosensweig resonance can be observed. The magnetized material starts to aglign along the field lines in vertical direction. The peaks lift up from the surface to get in line with the field. At the same time the peaks are repelling other material that has the same orientation in neighbouring peaks.
In this way a 2-dimensional structure of peaks is formed that is characterisic for the field strength and the concentration of the magnetic fluid.
In the following video the behavior of magnetic fluid is compared with the behavior of a few steel balls in the same magnetic field, they behave quite similar.
http://www.youtube.com/watch?v=sBsh7RbzNNI
|