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Name: angel
Status: student
Age: 18
Location: N/A
Country: N/A
Date: 1999 


Question:
can anything block magnitism?


Replies:
Yes, you can shield against magnetic fields using any magnetic material. One of the most effective shields is a material called mu-metal. The idea is to 'trap' all the magnetic lines of force within the metal and thus preventing it from affecting other objects in the area. To be completely effective the shield should completely surround the object you are trying to protect.

Bradburn


Electrical conductors attenuate a magnetig field. Superconductors exclude a magnetic field entirely. That is the physical basis for "magnetic levitation": magnetic fields actually repel superconductors.

Richard Barrans Jr., Ph.D.


you cannot really block magnetism, what "comes out" of a magnet (its field lines, in our imaginary world) must go back in somewhere. BUT you can redirect them with a magnetic material like soft iron. This is commonly done. If there is some instrument or machine that is sensitive to stray magnetic fields, even that of the earth, then that device can be wrapped in soft iron (there is a thing called mu metal, just iron really). It diverts the magnetic field away from the sensitive area.

Ross


Yes. Magnetic fields behave in much the same way as electric fields at an interface between two materials, though the characteristic of the materials that is important are different. For magnetic fields, the important characteristic is the magnetic permeability, and a high- permeability material like iron or mu-metal can be used to shield against a magnetic field. A superconductor is an even better shield.

Tim



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