What Happens to the Magnetic Field in a Hollow Ball of Hemispheric Magnets?

AI Thread Summary
When two hemispheric magnets with S on the outer surface and N on the inner surface are combined into a hollow ball, the magnetic field becomes complex. The inner surface's field lines do not connect to the outer surface, leading to no net magnetic field exiting the ball. However, field lines can still enter and exit at various points, indicating that the structure remains a magnet. Additionally, there is a phenomenon of "magnetic pressure" that attempts to push the two halves apart. Overall, the arrangement retains magnetic properties despite the unique configuration.
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There are two hemispheric magnets, both of them have S on the outer surface and N on the inner surface. If I put them together to form a hollow ball, assuming they are so close that no empty space in the interface, what happens to the magnetic field (inside and outside)?

Since magnetic field lines must start from N and end at S, what I think is that the field line will not "come out" from the inner surface any more as it cannot connect to the outer surface of the magnet. So this ball is not longer a magnet, is it right?
 
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That arrangement will have a complicated magnetic field. While no net field leaves the ball, there will be field lines leaving at some points and entering at others.
 
There will also be "magnetic pressure" trying to push the hollow ball apart (as would be felt while trying to push the two halves together). So it will still be a magnet. I'd love to be able to try this.
 
clem said:
there will be field lines leaving at some points and entering at others.

Do you mean the field lines leaving at the inner surface can pass through the ball somehow and enter at some points at the outer surface?
 
Yes.
 
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