Calculating Magnetic Field Strength for a Simple Bar Magnet

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To calculate the magnetic field strength of a simple bar magnet at a specific point on a plane, one must consider that there is no straightforward analytical solution available. The strength of the magnet cannot be determined solely by its dimensions and material properties. A suggested approach is to refer to Jackson's book, which provides equations for the field of a homogenously magnetized sphere as a potential approximation. The complexity of the problem indicates that further exploration and study may be necessary for accurate calculations. Additional questions may arise as the problem is examined more closely.
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If I have a simple bar magnet which is say 'w' x 'h' metres in dimension placed on a plane, say at cartesian coordinates (xM, yM), how can I work out the magnetic field strength at some arbitary point (x, y) also on that plane.



I've searched the internet but can only find equations to do with electomagnets or magnetism due to electic current. Nothing for a plane old chunk of iron.

I just need the equations, you can define the properties of the magnet such as how strong it is.

Thanks.
 
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The strength of a magnet is not defined by just its size and composition.

- Warren
 
It's not a trivial problem even though it looks like one. There's no analytical solution that I know of.
You can find the eqs. for the field of a homogenously magnetized sphere in Jackson's book (section 5.10), that might do as an approximation.
 
Thanks arcnets, I will check out the book. After looking at the problem some more I agree that it is far from trivial.

I'll post if I have any more questions.
 

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