How Can I Learn About Permanent Magnet Field Strengths and Interactions?

AI Thread Summary
To learn about permanent magnet field strengths and interactions, it's important to understand that the complexity increases with the geometry of the magnets. Manufacturers often provide rated strengths for their magnets, which can be a useful starting point. For practical measurement, using a coil of wire as an electromagnet can help compare field strengths without a gaussmeter. Visualizing the magnetic field in 3D space by plotting points and assigning colors for polarity can aid in understanding field shapes. Resources like Wikipedia articles on permanent and electromagnets can provide foundational knowledge for further exploration.
Wingwalker
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Im looking to do some projects with permanent magnets.

I don't have access to a gaussmeter and I'm wondering if there are any sites that have representations, descriptions or formulas for the field strengths of ferrite or neodymium magnets.

Also i need to learn about how magnetic fields from permanent magnets interact with each other in attractive and repulsive situations containing mulitple magnets.

Im guessing I am going to have a lot to learn as I have no formal physics education.

Any help enabeling me to understand this concept would be appreciated.
 
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Welcome to PF;
The interactions of magnets is very complicated unless you strive to keep the geometry simple.
Computing the field strengths of magnets is also not easy.
So the details will depend a lot on what you want to do with them.

Manufacturers will often tell you a rated strength for their products - read carefully.

The equations for electromagnets and magnetic induction are (a bit) easier - if I were you, I'd use a coil of wire to measure field strengths and run it as an electromagnet to compare strengths.

Try the wikipedia articles for permanent and electro-magnets as starting points.
 
Hi Simon,

Thanks for the reply. So, I have a N35 neodymium magnet 12mm x 12mm x 6mm with north and south being on the opposing 12 x 12 faces. If I were to plot out in 3d space the strength of the field at that a particular point and assign a colour to that point (red and blue for example) to represent its polarity then I could build up a visual representation of the magnet and its field. If I then repeated this for 3 other magnets of the same grade and same size but with one dimension changed, say changing 6mm to 12mm then 24mm and lastly 48mm I would get a get a data set that I could then use to determine the strength and field shape of a magnet that is 16mm. Correct?

I'm hoping that I am correct and his has been done before and there is some formula that can calculate this without me having to purchase a gaussmeter and do it myself, it seems pretty basic.

I'm reading through the wiki also
 
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