High School How is a magnetic field formed in a space surrounded by one pole?

[hongseok]

TL;DR

How is a magnetic field formed in a space surrounded by one pole?

There is a magnet in the shape of a hollow sphere. And the inner surfaces are all n-poles, and the outer surfaces are all s-poles. At this time, how is the magnetic field formed in the empty space of the sphere? There is no s pole for the magnetic force lines from the n pole to enter, so can magnetic force lines be created? Also, if only magnetic force lines are generated from the s-pole to the n-pole inside the magnet, the number of magnetic force lines entering and exiting the magnet must be the same, so won't it interact with magnets outside the spherical magnet? These may not seem to make sense. What actually happens in these situations?

 

[Vanadium 50]

There is a magnet in the shape of a hollow sphere. And the inner surfaces are all n-poles, and the outer surfaces are all s-poles

Thereis? Where is said magnet? One cannot build such an object.

 

[Dale]

TL;DR Summary: How is a magnetic field formed in a space surrounded by one pole?

There is a magnet in the shape of a hollow sphere. And the inner surfaces are all n-poles, and the outer surfaces are all s-poles. At this time, how is the magnetic field formed in the empty space of the sphere? There is no s pole for the magnetic force lines from the n pole to enter, so can magnetic force lines be created? Also, if only magnetic force lines are generated from the s-pole to the n-pole inside the magnet, the number of magnetic force lines entering and exiting the magnet must be the same, so won't it interact with magnets outside the spherical magnet? These may not seem to make sense. What actually happens in these situations?

One bar magnet is a dipole. Two bar magnets is a quadrupole. Four bar magnets is an octopole. Etc.

As you add more dipoles you get higher order multipoles. You do not get a monopole.

 

[Baluncore]

And the inner surfaces are all n-poles, and the outer surfaces are all s-poles. At this time, how is the magnetic field formed in the empty space of the sphere?

As the magnetic modules are assembled to form the shell, the existing magnetic field lines will pass between the modules. Energy will be required to assemble the modules, which will result in cancellation of the total magnetic field. Some magnets will be weaker than others, so the resulting field will be sum zero, with some minor N and S poles identifiable.