Determining magnetic force at a distance 1

[AgainstOdds]

Can someone point me in the direction of an equation to determine magnetic force at a given distance? I'm trying to determine what percentage of magnetic attraction or repulsion remains at a separating distance of 1cm, 2cm, 3cm, etc... Thank you.

 

[MagMike]

AgainstOdds: There are no equations to calculate force at a distance. FEA is required.

 

[prex]

AgainstOdds,
too much depends on the geometry of the magnetic setup, so no general rules can be provided.
For a horseshoe arrangement with a PM (or a coil), you can express the force exerted on the closing iron as a function of the gap, though it is known that, for gaps sufficiently large to be interested in, the actual force may be smaller than the theoretical one by a factor of 2 or more.
Come back if this is what you are looking for.

prex

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[Clyde38]

AgainstOdds,
Try this:

http://www.imsolution.com.au/magnet-formula.html