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Impedance

Impedance is the alternating-current opposition that combines resistance and reactance. In the symbolic method, Steinmetz represents it as a complex quantity:

Z=r+jxZ = r + jx

The OCR candidate in Chapter V places this directly after the discussion of current as a complex wave and the voltage required to overcome resistance and reactance.

Modern notation usually writes:

Z=R+jXZ = R + jX

where R is resistance, X is total reactance, and |Z| is impedance magnitude.

Z=R2+X2|Z| = \sqrt{R^2 + X^2}

Resistance is the power-consuming part. Reactance is the field-storage part. Impedance is the total relation between alternating voltage and alternating current when both effects are present.

E=ZIE = ZI

This is Ohm’s law restored for AC, but only after voltage, current, and opposition are treated as complex quantities with phase.

Ether-Field Interpretive Reading

Interpretive only: impedance can be read as the circuit-level expression of both dissipative opposition and field-storage opposition. Field-centered readers may emphasize the latter, but the source claim remains an engineering relation between voltage, current, resistance, and reactance.

What Steinmetz Is Doing Here

Impedance gathers resistance and reactance into one calculable AC opposition.

The current strongest source route is Theory and Calculation of Alternating Current Phenomena, with 313 candidate hits across 28 sections.

Modern Translation

Modern readers recognize it as complex impedance, but the source path shows why the geometric and physical split mattered.

This page currently tracks 1324 candidate occurrences across 13 sources and 154 sections.

Mathematical And Visual Route

Use R plus jX, magnitude, phase, voltage/current relation, and power-factor consequences.

Use the math/visual bridge lower on this page to jump into formula families, source visual maps, and candidate figure leads.

Interpretive Boundary

Field readings should connect reactance to storage and return, without confusing impedance with a literal material substance.

Layer labels stay active: source claim, modern equivalent, mathematical reconstruction, historical note, and interpretive reading are not interchangeable.

PassageHitsLocationOpen
Chapter 17: The Alternating-Current Transformer
Theory and Calculation of Alternating Current Phenomena
45lines 16521-17716read - research review
Chapter 5: Single-Phase Induction Motor
Theory and Calculation of Electric Apparatus
44lines 8555-10582read - research review
Chapter 16: Induction Motor
Theory and Calculation of Alternating Current Phenomena
42lines 13649-16361read - research review
Chapter 19: Alternating- Current Motors In General
Theory and Calculation of Electric Apparatus
39lines 21713-23905read - research review
  • Tracked vocabulary: Impedance.
  • Concordance: Impedance.
  • Source discipline: the table above is for reading and navigation; exact quotation still requires scan verification.
  • Editorial rule: expand this page by promoting scan-checked passages, equations, and diagrams from the linked workbench pages, not by adding unsourced generalizations.

Generated evidence layer: this dossier is built from the processed concept concordance. Counts and snippets are OCR/PDF-text aids, not final quotations. Verify against scans before making exact claims.

1324

Candidate occurrences tracked for this page.

13

Sources with at least one hit.

154

Sections, lectures, chapters, or report divisions to review.

Read this concept page through the linked source passages first. Use the dossier to locate Steinmetz’s wording, then add modern, mathematical, historical, and interpretive layers only with labels.

The strongest current source concentration is Theory and Calculation of Alternating Current Phenomena with 313 candidate hits across 28 sections.

The dossier is meant to turn a concept page into a reading path: begin with Steinmetz’s source wording, then use the research links only when you need candidate counts, snippets, mathematical reconstruction, historical context, or interpretive layers.

impedance, impedances

Impedance

Chapter 17: The Alternating-Current Transformer - 45 candidate hits

Source: Theory and Calculation of Alternating Current Phenomena (1916)

Location: lines 16521-17716 - Tracked concepts: Impedance

... transformer depends upon the primary e.m.f., which dependence can be represented by an admittance, the "primary admittance," Fo = g^i - jbo, of the transformer. The resistance and reactance of the primary and the secondary circuit are represented in the impedance by Zo = To + jxo, and Zi = ri + jxi. Within the limited range of variation of the magneti...
... The resistance and reactance of the primary and the secondary circuit are represented in the impedance by Zo = To + jxo, and Zi = ri + jxi. Within the limited range of variation of the magnetic density in a constant-potential transformer, admittance and impedance can usually, and with sufficient exactness, be considered as constant. Let no = number of...
Chapter 5: Single-Phase Induction Motor - 44 candidate hits

Source: Theory and Calculation of Electric Apparatus (1917)

Location: lines 8555-10582 - Tracked concepts: Impedance

... hus is proportional to the quadrature flux. At synchronism, the quadrature magnetic flux produced by the armature currents becomes equal to the main magnetic flux produced by the impressed single-phase voltage (approximately, in reality it is less by the impedance drop of the exciting current in the armature conductors) and the magnetic disposition of...
... olt-ampere excitation of the single- phase motor thus is the same as in the polyphase motor at the same induced voltage, and decreases to half this value at stand- still, where only one of the two quadrature components of magnetic flux exists. The primary impedance of the motor is that of the circuits used. The secondary impedance varies from the join...
Chapter 16: Induction Motor - 42 candidate hits

Source: Theory and Calculation of Alternating Current Phenomena (1900)

Location: lines 13649-16361 - Tracked concepts: Impedance

... em ; if r^ = secondary resistance per circuit, rt = a2 r{ = secondary resistance per circuit reduced to primary system ; if x± = secondary reactance per circuit, xt = a2 x\ = secondary reactance per circuit reduced to primary system ; if £/ = secondary impedance per circuit, z1 = azz\ = secondary impedance per circuit reduced to primary system ; that...
... rt = a2 r{ = secondary resistance per circuit reduced to primary system ; if x± = secondary reactance per circuit, xt = a2 x\ = secondary reactance per circuit reduced to primary system ; if £/ = secondary impedance per circuit, z1 = azz\ = secondary impedance per circuit reduced to primary system ; that is, the number of secondary circuits and of tur...
Chapter 19: Alternating- Current Motors In General - 39 candidate hits

Source: Theory and Calculation of Electric Apparatus (1917)

Location: lines 21713-23905 - Tracked concepts: Impedance

... it, r', consumes an e.n r'(, in phase with the current, and the total or effective resistance of the circuit is, therefore, r = r' + r", and the total e.m.f. consumed by the circuit, or the impressed e.m.f.. is: E = (r+jx)I = Z{, .where : Z = r + jx = impedance, in vector denotation, z = Vr* + i* = impedance, in absolute terms. If an electric circuit...
... urrent, and the total or effective resistance of the circuit is, therefore, r = r' + r", and the total e.m.f. consumed by the circuit, or the impressed e.m.f.. is: E = (r+jx)I = Z{, .where : Z = r + jx = impedance, in vector denotation, z = Vr* + i* = impedance, in absolute terms. If an electric circuit is in inductive relation to another electa circu...
Chapter 4: Induction Motor With Secondary Excitation - 37 candidate hits

Source: Theory and Calculation of Electric Apparatus (1917)

Location: lines 5555-8554 - Tracked concepts: Impedance

... As illustration is shown in Fig. 20 the load curve of a typical 100-hp. 60-cycle 80-polar induction motor (90 revolutions per minute) of the constants: Impressed voltage: ea = 500. Primary exciting admittance: Ya = 0.02 - 0.6 j. Primary self-inductive impedance: Zu = 0.1 + 0.3j. Secondary self-inductive impedance: Zi = 0.1 + 0.3 j. INDUCTION MOTOR 53...
... typical 100-hp. 60-cycle 80-polar induction motor (90 revolutions per minute) of the constants: Impressed voltage: ea = 500. Primary exciting admittance: Ya = 0.02 - 0.6 j. Primary self-inductive impedance: Zu = 0.1 + 0.3j. Secondary self-inductive impedance: Zi = 0.1 + 0.3 j. INDUCTION MOTOR 53 As seen, at full-load of 75 kw. output, the efficiency i...
Chapter 12: Frequency Converter Or General Alternating Current Transformer - 33 candidate hits

Source: Theory and Calculation of Electric Apparatus (1917)

Location: lines 14897-17124 - Tracked concepts: Impedance

... air gap in the magnetic circuit, to permit movability between primary and secondary, and thus they require a higher magnetizing current than the closed magnetic circuit stationary transformer, and this again results in general in a higher self- inductive impedance. Thus, the frequency converter and in- duction motor magnetically represent transformers...
... magnetic circuit stationary transformer, and this again results in general in a higher self- inductive impedance. Thus, the frequency converter and in- duction motor magnetically represent transformers of high ex- citing admittance and high self-inductive impedance. 104. The mutual magnetic flux of the transformer is pro- duced by the resultant m.m.f....
LayerWhat to add next
Steinmetz wordingPull exact source passages only after scan verification; keep OCR text labeled until then.
Modern engineering readingTranslate the source usage into present electrical-engineering or physics language without erasing the older vocabulary.
Mathematical layerLink equations, variables, diagrams, and worked examples when the concept has formula candidates.
Historical layerIdentify whether the term is still used, renamed, absorbed into modern theory, or historically obsolete.
Ether-field interpretationKeep interpretive readings separate from Steinmetz’s explicit claim and from modern physics.
Open questionsRecord places where the concordance suggests a lead but the scan or edition has not yet been checked.
  1. Open the highest-priority source-text passages above and verify the wording against scans.
  2. Promote exact definitions, equations, diagrams, and hidden-gem passages into this page with source references.
  3. Add related concept links, equation pages, and diagram pages once the evidence is scan checked.
  4. Keep speculative or Wheeler-style readings in explicitly labeled interpretation blocks.

Generated bridge: this section crosslinks the concept page with the formula atlas, figure atlas, source visual maps, and source formula maps. It is a routing layer, not final interpretation.

1031

Formula candidates routed to this concept.

143

Figure candidates routed to this concept.

6

Modern guide diagrams related to this concept.

Impedance, Reactance, And Admittance - Symbolic AC And Complex Quantities

Rotating Magnetic Field From Quadrature Fluxes

Modern reading aid for induction-machine field language in AC and Theoretical Elements sources.

symbolic-method, magnetism, phase, induction-motor

Open SVG - recreated visual index

Admittance Plane

Modern reading aid for conductance, susceptance, and reciprocal impedance.

admittance, conductance, susceptance, symbolic-method

Open SVG - recreated visual index

Engineering Number Plane

Modern reading aid for number, direction, and symbolic calculation in Engineering Mathematics.

complex-quantities, number, symbolic-method

Open SVG - recreated visual index

AC Symbolic Method Redraw Sheet

Modern redraw sheet for rectangular components, resultant addition, and quarter-period j rotation.

symbolic-method, complex-quantities, phasor, operator-j

Open SVG - recreated visual index

Phasor And Symbolic Method

Modern reading aid for vector and complex-number representation of alternating quantities.

symbolic-method, complex-quantities, phase, phasor

Open SVG - recreated visual index

Impedance And Reactance Triangle

Modern guide for resistance, reactance, impedance, phase angle, and symbolic quantities.

impedance, reactance, power-factor, symbolic-method

Open SVG - recreated visual index

CandidateFamilyOCR/PDF textRoutes
theory-calculation-transient-electric-phenomena-oscillations-eq-candidate-0272
strong-formula-candidate
transients-oscillationAt the moment 0 = 0, let the e.m.f. e = E cos (0 - 00) besource
research review
theoretical-elements-electrical-engineering-eq-candidate-0102
strong-formula-candidate
symbolic-ace = 2 7r/n$ sin r the instantaneous generated e.m.f.source
research review
theory-calculation-alternating-current-phenomena-1900-eq-candidate-0240
strong-formula-candidate
symbolic-acis r - j (x -f x0} = r = .6, x + x0 = 0, and tan S>0 = 0 ;source
research review
theory-calculation-alternating-current-phenomena-eq-candidate-0167
strong-formula-candidate
symbolic-acB = 6’ + jh” = 6(cos 13 + j sin /3)source
research review
theory-calculation-alternating-current-phenomena-eq-candidate-0294
strong-formula-candidate
symbolic-acis r - j {x + Xo) = r = 0.6, x -{- Xo = 0, and tan do = 0; thatsource
research review
theory-calculation-electric-apparatus-eq-candidate-0028
strong-formula-candidate
symbolic-ac= - J = (tan a - j) (7)source
research review
theory-calculation-transient-electric-phenomena-oscillations-eq-candidate-0276
strong-formula-candidate
transients-oscillationSince e = E cos (0 - 00) = impressed e.m.f.,source
research review
theory-calculation-transient-electric-phenomena-oscillations-eq-candidate-0296
strong-formula-candidate
transients-oscillationi = -z | cos (I? - 00- 0J- i~x° cos (00 + OJ j (9)source
research review
CandidateCaption leadSectionRoutes
theory-calculation-alternating-current-phenomena-fig-010
Fig. 10
21 Fig. 10. phase angle — /3’ = — (a’ — ??]) = 10 A, and the equations ofChapter 4: Vector Representationsource
research review
theory-calculation-alternating-current-phenomena-fig-031
Fig. 31
CAPACIir AND RESISTANCE Fig. 31. Fig. 32.Chapter 6: Topographic Methodsource
research review
theory-calculation-alternating-current-phenomena-fig-033
Fig. 33
RESISTANCE AND LEAKAGE Fig. 33. 16 I TRANSMISSIONChapter 6: Topographic Methodsource
research review
theory-calculation-alternating-current-phenomena-fig-035
Fig. 35
RESISTANCE AND LEAKAGE Fig. 35. their difference of phase are plotted in Fig. 35 in rectangularChapter 6: Topographic Methodsource
research review
theory-calculation-alternating-current-phenomena-fig-049
Fig. 49
7 1.8 Fig. 49. The sign in the complex expression of admittance is always opposite to that of impedance; this is obvious, since if the cur-Chapter 8: Admittance, Conductance, Susceptancesource
research review
theory-calculation-alternating-current-phenomena-fig-051
Fig. 51
Eo E Fig. 51. MChapter 9: Circuits Containing Resistance, Inductive Reactance, And Condensive Reactancesource
research review
theory-calculation-alternating-current-phenomena-fig-052
Fig. 52
Eo Fig. 52. Fig. 53.Chapter 9: Circuits Containing Resistance, Inductive Reactance, And Condensive Reactancesource
research review
theory-calculation-alternating-current-phenomena-fig-053
Fig. 53
Fig. 52. Fig. 53. 2. Reactance in Series with a CircuitChapter 9: Circuits Containing Resistance, Inductive Reactance, And Condensive Reactancesource
research review