Magnets, barricade, magnetic field
To clarify you can NEVER BARRICADE A MAGNETIC FIELD in the traditional sense of the word barricade (see below). In physics, things such as gamma or alpha rays can be shielded because they have mass (and presumably velocity). Thus, some materials can block their movement due to the material's intrinsic nature. However, a magnetic field is just that: a field. Due to the nature of magnets (read: they have a north and south pole), magnetic field lines always run CONTINUOUSLY from the north to the south pole. Unlike charged particles, such as the electron, the monopole version of the magnet is, as of yet, undiscovered. Let me repeat: there are no magnetic monopoles. Thus, the magnetic field lines go from one pole to the other. End of story. In layman's terms, magnetic fields are CONSTANT and unblockable. HOWEVER!! Some engineers are very clever and have devised materials that can bend magnetic fields AROUND objects that require magnetic shielding. For the most part, materials with high permeability (Google the term if you don't know it) are used in magnetic shielding.
i dont think so i think you can make the field stronger but smaller though. limit the distance but increase the strength. thats just a guess though
If you mean shield against a magnetic field, yes you can. Lots of materials will do that. On the other hand, I have seen a magnet field cancellation system, at the University of California at Davis that countered the magnetic field of the earth. It was used for a beta-ray spectrometer to produce a magnetic field-free environment. About 6 feet in diameter, it looked like a wire-frame model of the earth build out of aluminum channel. Channels for longitude (maybe about 6) and for latitude (maybe about 4). Each channel carried wires whose currents would cancel out the fields of the earth. Time for this was about 1957-58. I saw it on a high school field trip. No idea how successful it was.
