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Ch 4 and Ap S REVIEWED
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A short working note by Phil, dated 9/22/14 and marked reviewed on 9/24/14 and stored in Appendix S. It records that trial averaging of C, 1/V and 1/K was dropped, and that the final appendix keeps only the averaging bracket. It also asks whether the inductance Le is real, noting that the equality KL = K forces this, and discusses possible complex phases in the charge density ρ1 and potential φ1 in Chapter 4.
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Ch 4 and App S PhL 9.22.14
Two interesting items here.
1. I was trying out averaging C and 1/V and 1/K, but that did not turn out to be useful in the end, so the final Appendix S only contains something called < > and then G(x1,x2) and C(x1,x2) are never mentioned and are not useful at all.
2. I noted that Le really ought to be complex, but in the end it is KL = K that forces it to be real, and this equality survives the averaging and now appears at the end of Appendix S.
Reviewed on 9/24/14 and stored in Appendix S.
Try this functional definition
C'(x1,x2) ≡ q(z) / V(x1,x2) = 4πξd / K(x1,x2)
Decompose C'(x1,x2) into its real and imaginary parts,
C'(x1,x2) = G(x1,x2) + jωC(x1,x2)
Double-averaging these equations gives
C' = q(z) * <> = 4πξd <>
C' = G + jωC
How do I connect this with the main line progression leading to the new TL equations? There we obtain
y ≡ jβd2/(ωLe)
which we could decompose into real and imaginary parts like so
y = G + jωC G ≡ Re[y] etc
Question: In Chapter 4 when I do this
W(z) = Le i(z)
do I know that Le is real?
Go back to
φ1(x,ω) = ∫ ρ1(x',y',z',ω) dx'dy'dz' . R = |x - x'| (4.1.1)
Now ρ1 could have some complex phase, and then so could φ1. And of course the expo is complex. You really must allow that everything could have a phase! How about
ρ1(x,y,z) = α1(x,y) q1(z) . (4.1.2)
Is this physical real stuff or could things be complex?
ρ1(x,y,z,t) = ρ1(x,y,z) ejω1t ρ1(x,y,z) = physical at some instant in time = real ?
ρ1(x,y,z,ω) = ρ1(x,y,z) 2πδ(ω-ω1)
But things often have phase depending on r.