A point between 2 magnets, what remains constant at that point?

AI Thread Summary
In the discussion about the magnetic and electric fields between two fixed magnets and charges, it was determined that the magnetic field strength (H) and magnetic flux density (B) will change depending on the material placed at the midpoint, while the magnetic motive force (MMF) remains constant. Similarly, for electric fields, the electric field strength (E) varies with the material, while the electric displacement field (D) may remain more consistent across different materials. The fundamental driving forces are identified as MMF for magnetism and EMF for electricity, rather than B, H, E, or D, which are influenced by the medium. The example of a solenoid with an iron core and air gap illustrates that while magnetic flux can be constant, the values of H and E will differ across materials. Ultimately, the discussion emphasizes the distinction between fundamental forces and field variables influenced by material properties.
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a fixed spatial point between 2 fixed magnets. if I place different blocks of material on that point, is the H that will remain the same? or is it the B? or just the MMF (magnetic motive force), while B and H will always change depend on the material placed?

the same question for E, D, and EMF between 2 fixed charges.

thanks
 
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I am sorry, I don't understand, was the question itself too naive? but I m just asking for a "yes" or "no" really. I was trying to understand the medium independent, fundamental driven force of E or M field.
 
It depends on the shape and orientation of the material.
Usually, both B and H will change in the vicinity of the material.
 
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And, both B and H will change at the point of interest INSIDE of the material as well right? The same applies for E and D too right?

So, none of B or H or E or D are "fundamental qualities". Only the EMF and MMF are. Meaning: only MMF ( N*i) is the fundamental "driver", while B and H will vary with the properties of different materials.

I was looking at a solenoid with an iron core inside. the iron core has an air gap inside. once the MMF was turned on, a constant flux will flow thru the core and air gap (ignore fringing), so B's are the same for air gap and core but H's are different.
I am guessing some similar situations would apply for E and D as well. D will remain the same thru out different materials but E actually varies.
 
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