Find magnetic field from temporary magnet

AI Thread Summary
The discussion focuses on finding the magnetic field strength from a temporary magnet and the force between a magnet and a piece of iron. A formula for magnetic force is provided, but the user is struggling to determine the magnetic field 'H' of the iron. It is suggested that the second magnet can be approximated to produce a magnetic field similar to the field in its vicinity without the magnet. For larger distances, the magnet can be treated as a dipole, allowing the use of dipole formulas for approximation. The conversation highlights the complexity of calculating magnetic fields in such scenarios.
SirHall
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What I've not been able to find after literally spending several hours researching is if you can find the formula to find the magnetic field strength from a temporary magnet. Or, to be put in better terms, what would be the force between two objects if one is a magnet and the other is something like a piece of iron? I've found ##F=\frac{KBH}{d^2}##
Where:
F = Magnetic Force
K = Magnetic Permeability
B = Magnetic Field
H = Second Magnetic Field

What I haven't been able to find however is how to find the magnetic field of 'H', or the magnetic field of the 'iron'.
Thanks for answers
 
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It is complicated. To get some rough approximation, you can assume that the second magnet will produce a magnetic field as strong as the field at its place without the magnet.
 
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mfb said:
It is complicated. To get some rough approximation, you can assume that the second magnet will produce a magnetic field as strong as the field at its place without the magnet.
Thanks, and if it's not too much to ask, would there be a way to approximate or find that?
 
Approximate what, the field from the magnet at that point? If the distance is large enough, you can approximate your magnet as a dipole and use the formula for dipoles.
 

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