Can't understand why the unit of Reluctance is At/Wb

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Homework Statement


I can't figure out why the unit of Reluctance is At/Wb and not (At/Wb)m2
This is what I have from my textbook, with the red oval area being the part that I'm totally confused about
Untitled.png

Homework Equations

The Attempt at a Solution


So the m/m cancels out to 1 making it
R=1/(Wb/At·m2)
which is = (At·m2)/Wb
then I have no idea what happened so that m2 vanished and R became At/Wb

Please help me clear up my confusion
I can't sleep scratching my head T_T
Thanks a bunch!
 
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road2knowledge said:
I can't figure out why the unit of Reluctance is At/Wb and not (At/Wb)m2
As your book says, reluctance is analogous to resistance in electrical circuits. Similarly, flux is analogous to current and mmf (Ampere turns) is analogous to voltage.
 
Note the division operator:
upload_2016-5-6_8-5-30.png

The underlined bit is in the denominator of the denominator, so to speak. Hence it can be "promoted" to the numerator of the overall expression.

upload_2016-5-6_8-11-58.png
 
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gneill said:
Note the division operator:
View attachment 100341
The underlined bit is in the denominator of the denominator, so to speak. Hence it can be "promoted" to the numerator of the overall expression.

View attachment 100342
OHHHHHHH!
Thank you so much!
I think I'll need to go back to secondary algebra for a bit of revision :(