As shown in the figure attached.
If both have the magnetization M, what will the B field and H fied for each object look like? why?
I have no hint how to answear this question, can anyone help?
any reply highly appreciated.
I assume that the picture means that M is constant in the material with the direction shown.
B and H are determined by the boundary conditions at the surfaces and constrained by the relation B-H=4pi M (in gaussian units).
Permeability and susceptibility are meaningless for this case.
For the disk, B=2pi M and H=-2pi M, because the BC at the ends dominates.
For the rod, B=4pi M and H~0 for most of the length, but near the ends the disklike BC dominates.