I Is total flux linkage λ=dΨ*Ienclosed/I or λ=N*Ψ?

AI Thread Summary
The discussion centers on the formulas for total flux linkage in different geometries, specifically comparing coaxial cables and solenoids. The formula dλ=dΨ * Ienclosed/I is used for coaxial cables, while λ=N*Ψ is applied for solenoids. There is confusion regarding the application of these formulas, particularly the role of Ienclosed/I in the coaxial case. Participants seek clarification on the context of the coaxial cable analysis, questioning whether it relates to telegrapher's equations or full wave-guide theory. The need for clear definitions of symbols, such as Ψ, is emphasized for better understanding.
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I don't understand why we multiply by Ienclosed/I the total flux linkage
In Sadiku, he used the formula dλ=dΨ * Ienclosed/I
to determine the total flux linkage for coaxial cable for ρ<a and for a<ρ<b, but I applied this formula for the solenoid and it didn't work, the way that works for the solenoid is by using λ=N*Ψ.

So why we multiply by Ienclosed/I in the coaxial cable?
 
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Without context and even a definition of your symbols I have no clue what you are talking about. E.g., are you looking at the coax cable from the point of view of the "telegrapher's equation", which is a quasistationary approximation, or the full wave-guide theory a la Maxwell and Hertz? What's ##\Psi##?
 
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