Force Exerted on Ferromagnetic Object by Permanent Magnet

AI Thread Summary
The discussion revolves around calculating the force exerted by a permanent magnet on a ferromagnetic object at varying distances. The original poster seeks assistance in creating a spreadsheet to explore different variables, including magnet grade, size, and the composition and size of the ferromagnetic object. There is consensus that the shape of the magnet significantly impacts flux density, complicating calculations. Participants note that precise calculations are challenging and often yield only rough estimates, suggesting an experimental approach may be more effective. Overall, the conversation highlights the complexities involved in magnetic force calculations and the preference for trial and error methods.
korneld
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Hello everyone. There is a little project I could use some help with.

I would like this done in a spreadsheet, so I can mess around with different values.

The Problem:

On one hand, I have a permanent magnet and, on the other, I have a ferromagnetic object. I want to find out the force the magnet is exerting on my object from any given distance.
If I’m not mistaken, one of the bigger issues here is the shape of the magnet, because that can affect flux density. Let’s work with a nice, generic shape.

The values I’d like to play around with are:

  • the grade of the magnet
  • the size of the magnet
  • the composition of the ferromagnetic object
  • the size of the ferromagnetic object
  • the distance between the two

I want to keep it simple. I don’t need the spreadsheet to have all the information stored on all neodymium magnets from N27 to N64. It should just tell me the different inputs it needs, and I’d be more than happy to look them up. The same goes for the ferromagnetic object.

Thanks in advance.
 
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Hello.. I have a very similar problem. Did you make any progress with this? No one on the internet seems to no the answer.. hehe
 
No, unfortunately everyone pretty much ignored it. Not sure why. I think, though, that it's probably best to do this experimentally. Calculations for this stuff can be difficult I'm told, and ultimately inaccurate.
 
Thanks for the reply.
Yup, the calculations do seem to be complex and even then, if the equations are solved, they only give rough estimates. :(
Trial and error it is then..
 
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