What is permanent magnet B field equation?

AI Thread Summary
To calculate the magnetic field (B) between two permanent magnets positioned 10mm apart, with each magnet having a core intensity of 1.3T and a surface intensity of 0.6T, one can use the formula for the electric field (E) due to a uniformly charged disk, as the B field behaves similarly under certain conditions. The B field at a distance of 5mm from the face of one magnet can be approximated as the sum of the fields from both magnets, effectively doubling the value. For precise calculations, it is essential to consider the dimensions of the magnets and their respective intensities. The relevant formula can typically be found in standard physics textbooks. This approach provides a basis for calculating the magnetic intensity between the magnets at the specified distance.
ShahinPhD
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I'm looking for an equation to calculate Tesla (B) between two permanent magnets with distance of 10mm.

Magnets are located in front of each other; disk shape and intensity of each is 1.3T in its core, and 0.6T on surface, so I'm interested how to calculate the B between them in distance of 5mm from each one (10mm between 2 magnets).

Please help me to find proper calculation.
Thanks in advanced.
 
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If the magnets are much longer than 5mm, the B field 5mm from the face of one magnet is the same as the E field 5mm from a uniformly charged disk with charge density
\sigma=M where M=13,000 gauss (all in Gaussianl units). Just double it for two magnets.
 
Thanks for your fast response.
It seems OK, but in a short form I'm looking for a formula to calculate the Tesla in distance between two magnets.
Suppose we have some parameters: dimensions of magnets, power of magnets in core and surface, distance between them; so how can we use a formula to calculate intensity between magnets in some distance?

(Frankly I'm looking for a formula to use for my calculations)
 

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The on axis formula for E due to a uniformly charged disk is in most (even elementary) textbooks.
 
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