Surface field vs pull force(attraction force) of multiple magnets?

AI Thread Summary
The discussion centers on the observation that multiple magnets can exhibit the same surface field while having varying pull forces. This discrepancy is attributed to differences in the size and dimensions of each magnet, which affect their overall magnetic strength. The pull force increases with the size of the magnet, despite the surface field remaining constant. Participants suggest plotting pull force against linear dimensions and cross-sectional area to analyze the relationship further. Understanding these factors is crucial for applications involving magnet selection and performance.
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In the following "semi" table, is a group of magnets,
all seem to have the same Surface field but all different pull force(attraction/repulsive force at maximum with gap = 0).
How is it possibile to have the same S.field rate but different forces? Is it due to the size of each magnet?


Magnets Length Width Thickness Surface Field Pull Force
(Gauss) (lb)

B444 1/4 " 1/4 " 1/4 " 5754 4.25
B666 3/8 " 3/8 " 3/8 " 5754 10.07
B888 1/2 " 1/2 " 1/2 " 5754 18.71
BCCC 3/4 " 3/4 " 3/4 " 5754 40.59
BX0X0X0 1 " 1 " 1 " 5754 76.41
 
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X Y A B C D

X = Magnet
Y = Length"
A = Width"
B = Thickness"
C = Surface field (Gauss)
D = Pull force (lb)
 
Try plotting your pull force versus linear dimension and see what you get. How about pull force versus
cross sectional area?
 

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