. The London, Edinburgh and Dublin philosophical magazine and journal of science. ctive balance is indicated in each case beside thefigure. The zero deflexion condition for steady currents Phil. Mag. S. 6. Vol 20. No. 116. Aug. 1910. Y 314 Dr. Sumpner and Mr. Phillips on a holds necessarily in the three cases oh figs. 2, 4 and G ; but atroublesome special adjustment is needed in the case of fig 3;while in the cases of figs. 5 and 7 the adjustment for steady Fiff. 2. W/WVVWWh-AA/WW Kft^KA. Fiff. 3. l2 rt M/WWV ^^iW-A/WWV AAAAA/V-1 11,+r, K;+r_; Fiff. 4. M, M ^3_£—^i^M/WWV— imr s rz M/WV\Ar-1-JV
. The London, Edinburgh and Dublin philosophical magazine and journal of science. ctive balance is indicated in each case beside thefigure. The zero deflexion condition for steady currents Phil. Mag. S. 6. Vol 20. No. 116. Aug. 1910. Y 314 Dr. Sumpner and Mr. Phillips on a holds necessarily in the three cases oh figs. 2, 4 and G ; but atroublesome special adjustment is needed in the case of fig 3;while in the cases of figs. 5 and 7 the adjustment for steady Fiff. 2. W/WVVWWh-AA/WW Kft^KA. Fiff. 3. l2 rt M/WWV ^^iW-A/WWV AAAAA/V-1 11,+r, K;+r_; Fiff. 4. M, M ^3_£—^i^M/WWV— imr s rz M/WV\Ar-1-JVVW\ArJ M, M R1+^1 E2+^ currents is impossible. In these figures capacities, self-inductances, and mutual inductances are respectively denotedby the letters K, L, M ; resistances are indicated by theletters R, r, and S ; while the indicator is denoted by Galvanometer for Alternate Current Circuits. 315 All these methods may be used with the present instru-ment for steady inductive balances on alternate currentcircuits, and the same formulae apply to the zero deflexion. M/WWV~M/WW\H M 11, + r, ~B,2 + ra Fiff. 6. M H/WWV R K M R-4-r = KS. Fig. 7. L r ■sisis^ 711. C. A/WWV— >-Ljvwwv-1 R KS = R-f-i condition, provided (i.) the alternate voltage V applied to thefield-coil of the instrument also causes the current A throughthe bridge conductors, (ii.) the alternate current A is madeessentially cophasal with V by the use of suitable non- Y2 316 Dr. Sumpner and Mr. Phillips on a inductive resistances as indicated by the zigzag lines in thefigures, (iii.) the moving coil o£ the instrument is placeddirectly across the bridge (using a reversing key whendesirable). It results from the special properties of the instrumentthat the flux in the gap o£ the electromagnet is in quadraturewith the applied voltage (and thus in quadrature with A).The inductances or capacities produce voltages or currentsalso in quadrature with A, and thus in phase with the flux,so that
Size: 2769px × 902px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1840, booksubjectscience, bookyear1840
