Magnetic field lines for a hollow cylinder Given the magnetic potential (phi) for a cylinder with a hollow inside in a constant magnetic field b0, we were able to determine the magnetic feild strength for a horizontal slice of the cylider. Setting the size of the cylinder at 1, and the hole inside to .5 the following graphs were obtained of the magnetic feild lines.

This is the situation when mu=0 (The substance is not susseptable to magnetic fields) As we expect the field lines avoid the entire cylinder.

This is the case when mu=.5 The lines to go thru the material, but there is no effective sheilding of the interior of the cylinder.

As the value of mu increases (here it is 30) the lines are all crowded into the edge of the cylider itself, leaving the interior free of the magnetic field.