Magnetic Reluctance: Correct Equation

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The correct equation for magnetic reluctance is debated, with two formulas presented: R = l / (μA) from Wikipedia and R = l / (μ₀μA) from a textbook. The Wikipedia formula is considered accurate, while the textbook may be misusing μ to refer to relative permeability, which could lead to unit inconsistencies. Clarification on the distinction between absolute and relative permeability is essential for understanding the equations. The discussion emphasizes the importance of verifying sources and definitions in physics. Accurate comprehension of magnetic reluctance is crucial for applications in electromagnetism.
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Which is the correct equation for Magnetic Reluctance ?

R = Reluctance
l = Length
A = Area
\mu = Magnetic Permeability of the material
\mu_0 = Magnetic Permeability of free space (4\pi \times 10^- ^7 tesla/ampere turn)

R = \frac {l} {\mu A} as stated on Wikipedia or R = \frac {l} {\mu_0 \mu A} as stated in my textbook.
 
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The Wikipedia formula looks correct. Are you sure your book isn't using \mu to mean relative permeability (which is just a ratio)? (If not, the units would make no sense in your book's formula.)
 
Thanks very much that would be it. "Relative Permeability"
 

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