40150_37

375 TABLES 370-406.-VAKIOUS ELECTRICAL CHARACTERISTICS OF MATERIALS The fundamental electrical and magnetic definitions and the values of the practical units of current, voltage, and other electrical quantities, have been given (Tables 2-5). Some data will now be presented on electrical characteristics of various materials. T A B L E 370.-THE EFFECT O F ELECTRIC CURRENT ON T H E H U M A N BODY'@* Some thought must be given to the electrical characteristics of the human body, since careless handling of electric circuits is very dangerous. The regular 120-volt circuit is dangerous, and any voltage above this increases the hazard. No bare contacts should be permitted where anyone might come in contact with them. A C (60cycles) DC Threshold of perception ....................................... 1 ma ...... 5 ma muscular decontrol .............................. 15 ......<70 danger to life .................................. 20 ...... 80 fibrillation (almost certain death). ................ 100 ........ Since the resistance of the human body for direct current (hand to foot or hand to hand), neglecting the contact resistance, is 5,000-10,000 ohms, good contact with electric circuits must be avoided. For alternating current the resistance is much lower. Bell Laboratories Rec., 'sea Cromwell. J. C., Origins and prevention of lahoratory accidents, 1950; p. 318. June 1936; Johns Hopkins University, Report of Electrician, November 1934; Journ. Franklin Inst., vol. 215, p. 1, 1933. T A B L E 371.-TRIBOELECTRlClTY Part 1.-The tribo-electric series The following table is so arranged that any material in the list becomes positively electrified when rubbed by one lower in the list. The phenomenom depends upon surface conditions and circumstances may alter the relative positions in the list. 1 Ashestos (sheet). 2 Rahhit's f u r hair ( H g ) . 2 Glass (com6n. tubing). 4 Vitreous silica, oppossum's fur. 5 Glass (fusn.). 6 Mica. 7 Wool. 8 Glass (pol.), quartz (pol.), glazed porcelain. 9 Glass (broken edge), ivory. 10 Calcite. 11 Cat's f u r . 12 Ca, Mg, Pb, fluorspar, borax. 13 Silk. 14 Al. Mn, Zn, Cd. Cr, felt, hand, wash-leather. 1 5 Filter paper. 16 Vulcanized fiber. 17 Cotton. 18 Magnalium 19 K-alum, rock-salt, satin spar. 20 Woods, Fe. 21 Unglazed. porcelain, salammoniac. 22 K-hichromate, paraffin, tinned-Fe. 23 Cork, ebony. 24 25 26 27 28 29 30 31 32 33 34 Amber. Slate chrome-alum. ShellHc, resin, sealing-wax. Ebonite. Co. Ni, Sn, Cu, As, Bi, Sh, Ag, Pd, C, Te, Eureka, straw, copper sulfate, brass. Para rubber, iron alum. Guttapercha. Sulfur. Pt. Ag. Au. Celluloid. Indiarubber. Part 2.-Triboelectric series in voltage o f a number of metals as compared with silica (as 0 ) lrn Ni Ph Fe Cr co Au Pt ............... ...+ 15 ..................+ ................ .+17 ................. + .................. + .................. + .................. + cu Bi 9.3 8.5 .................+ 7 ..................+ 4.8 .................. + 3.3 1.4 7.8 TI .6 Zn Sn Se ......... 0. ......... .1 .................- 3 ................. 7.3 .................- 7.7 'n Shaw, P. E., and Leavey, E. W. L., Proc. Roy. SOC., r vol. 138, p. 506, 1932. SMlTHSONlAN PHYSICAL TABLES 376 TABLE 372.-CONTACT DIFFERENCE O F POTENTIAL I N VOLTS * Solids with liquids and liquids with liquids in air Temperature of substances during experiment about 16°C C Cu I:e Pb 1 X q Pt Sn Zn .\malg. Zn Brass Distilled water ............ - .01 ! to 269 tn [ .285 148 (-.lo5 . . . . . . . . . . . . . . . sp.gr. 1.087 . . . . . . . .lo3 . . . . . . ... . . . . . . . . . . . . . . . CuSO, satsol. . . . . . . .070 ...... Sea salt sol. . . . -.435 . . . --.856 -.334 -.565 1.18 at 20°C . . . . . . . --.475 -.605 ... -.348 ,059 --.364 -.h37 N H L I . sat.sol. . . . . . . -.396 -.h52 -.189 ZnSO, sol. 1.125 . . . . . . -.238 ...... at 4°C . . . . . . . . . . . . . . . . . . . . . . . .. --.430 -.284 . . . -,200 ...... ZnS04 sat.sol. . . . . . . . . . . One part H 2 0 ... . . . . . . -.444 ...... 3, sat. ZnSO. . . . . . . . . Strong HzSO, in water : . . . . . . -.344 . . . . . . . . . . . . 1 to20 by wt. . . . . . . . . . . . about 1 to 10 by VOI. ....{-,035 ... ... . . . . . . . . . . . . . . . -358 ... . . . . . . . . . .429 ... I t 0 5 by wt. ...... . . . . . . ...... + 5 t o 1 by wt. Con. HSO, ...... ...... ... . . . -.120 . . . -.25 ...... -.016 1.3 to . . . . . . ,848 ... 1.298 1.252 1.6 Con. HNO, . . . . . . . . . . . . . . . . . . ,672 . . . . . . . . . . . . ... Mercurous sulfate paste, Hg, + ,475. Sat.CuS04sol., H,O, - .043 ; sat.ZnS04sol., ,095 ; 1 pt. H20,3 pt. ZnSOI ,102. 1.298; sat.aluin.sol., + 1.456 ; CnS04sat.-t1.269 ; ZtiSO.sat.sol., Concentrated H,S04, H,O, 1.699. { .55 to .85 1.113 ... { ?:. + + + + Everett, Units and physical constants: Table of Ayrton and Perry's results, prepared by Ayrton. TABLE 373.-THERMAL ELECTROMOTIVE FORCE OF A L U M I N U M VERSUS P L A T I N U M 'O Tcmperature versus emf "C 0 20 40 60 80 100 120 140 180 200 220 '40 i 60 +.062 .135 .218 ,312 .416 .529 .651 .781 .919 1.064 1.216 .ooo mv "C mv "C mv 240 360 380 400 420 440 460 1.374 1.538 1.708 1.884 2.065 2.252 2.444 2.641 2.843 3.050 3.262 3.480 480 500 520 540 560 580 600 620 640 660 3.703 3.931 4.164 4.403 4.647 4.896 5.150 5.409 5.673 5.942 Nat. Bur. Standards Circ. 346, 1927. SMITHSONIAN PHYSICAL TABLES 377 T A B L E 3 7 4 . 4 O M P O S I T I O N A N D ELECTROMOTIVE FORCE OF VOLTAIC CELLS The electromotive forces given in this table approximately represent what may be expected from a cell in good working order, but, with the exception of the standard cells, all of them are subject to considerable variation. Part 1.-Double Name of cell Negative pole fluid cells Positive pole Solution emf in volts Solution Runsen Chromate Dartjell Am;lg.?p " I' 1,HxSOd ;12,H20 C I' t' I' I.' 'I " 'I " I' " Grove " " 'I " '1 ' I " 1' " " '1 'I " " I' Partz 'I 12,K,Crz0, ; 25,HzSO, ; 100,HzO I,H,SOI ; 12,HzO 1.H&O, : 4.H2O 1;H;S04; 12,HzO 5% sol.ZnSO4 ;6H,O 1NaCl ; 4 parts Hz0 IHZSO,; 12Hz0 Sol.ZnSO4 H z S 0 4 ; dens. 1.136 sol. HzSO, ; dens. 1.134 H 2 S 0 4 ; dens. 1.14 sol. H & 0 4sol. ; dens. 1.06 NaCl sol. SOI.MKSOI Part 2.-Single Fuming HNO, H N O , ; dens. 1.38 1,HzSOI ; 12,HzO 1.94 1.86 2.00 cu Pt 1: :: Carbon * Coqper + 12,KzCrz0,:100,HzO 2.03 Sat.sol.CuS0. ; 5 , H ~ 0 1.06 1.09 1.08 1.05 Fuming HNO, 1.93 HNO, ; dens. 1.33 1.66 1.93 Concent. H N O:, HNO.: dens. 1.33 1.79 HNO,; dens. 1.19 1.64 " 1.61 1.33 1.88 Sol.KzCrzOi 2.06 I' I' fluid cells 1-eclanche Amalg. ?p Chaperon Etlisoii-Ixlande " Z 11 AgCI Law Dry cell I' Sol.NH,CI Sol.KOH 23% sol.NH,Cl 15% ' I " Poggydorff Regnault Volta coude $yialg. Zn " " Zn 1 1)t. 2110, 1)t. NH,CI, 1 3 pts. plaster of paris, 2 nts. ZnCL and water to make a paste Sol.KzCrrOi ; 12KzCr201 25HA0, : 100,HzO lHzSO,; 12HzO; lCaSO4 Cd HZO Silver i Cat-mi .98 .70 1.02 1.37 1.3 1.46 1.08 2.01 .34 .98 % Depolarizer: Silvcr cu Deliolarizer: Manganese peroxide with powdered carhon. chloride. t Dcpo1:irizer: CuO. Part 3.-Secondary cells Ph accumulator Regnier (1) " Ph Cu H,SO, sol. of density 1.1 CUSo,; HzS04 Z n S 0 4 sol. H S O , : dens. about 1.1 K O H 20% sol. Pl$L 2.25 1.hl, to .85 2.36 2.50 1.1 mean 2.0779 130 5.2 1.89 2.2070 73 (2) Amalg.Zn " " Main Edison i; H: J ;O A nickel oxide Fe $ F. Streintz gives the following value o f the ternlwrature v:iri;itions & d! t ;It different stages uf charge: emf d E / d t X 10" 1.9223 140 1.9828 228 2.0031 335 2.0084 285 min5 255 Dolezalek gives the following relation hetween emf and acid concenti-ntion: Percent H S O , 64.5 52.2 35.3 21.4 emf "C 2.37 2.25 2.111 2.00 (contintled) SMITHSONIAN PHYSICAL TABLES 378 T A B L E 374.-COMPOSITION A N D E L E C T R O M O T I V E FORCE O F V O L T A I C C E L L S (concluded) Part 4.-Standard cells Clark Weston /I 1Very I Z n + Hg Cd-tHg ZnSO. CdSO4 Paste HzSO*+Hg Paste CdSO4+Hg 1.434 1.0185 low temperature coefficient. T A B L E 375.-DIFFERENCE O F POTENTllAL B E T W E E N M E T A L S I N SOLUTIONS O F SALTS The following numbers are given by G. Magnanini for the difference of potential in hundredths of a volt between zinc in a normal solution of sulfuric acid and the metals named at the head of the different columns when placed in the solution named in the first column. T h e solutions were contained in a U-tube, and the sign of the difference of potential is such that the current will flow froin the more positive to the less positive through the external circuit. S t r e n g t h of the solution i n g r a m molecules ner liter Zinc Cadmium Lead Tin Copper Silver No. of molecules Salt Difference of potential in centivolts 1.o 1.o 1.o 1.o 1.o .5 .5 HzSO, NaOH KOH -32.1 -42.5 1.4 - 5.9 11.8t 11.5 23.9f 72.8 1.8 - .5 - 6.1 41.0: - 1.2 4.5 .o 36.6 19.5 15.5 35.6 24.1 31.9 32.3 42.8 61.1 34.7 37.1 33.6 80.8 32.5 35.2 38.3 39.3 35.6 39.9 40.7 32.4 22.5 31.9 31.7 32.1 28.7 41.6 39.7 41.3 31.5 51.3 31.8 32.0 50.8 45.3 42.6 51.0 41.2 78.4 51.0 53.2 50.7 81.2 52.8 50.2 50.6 51.7 47.5 53.8 51 3 51.3 41.1 51.2 47.2 51.6 41.0 73.1 61.3 61.6 51.5 51.3 .2 -1.2 51.4 45.7 31.1 40.9 40.9 68.1 40.9 57.6t 41.2 130.9 52.7 49.0 48.7 52.8 49.9 57.7 50.9 50.9 50.8 50.3 52.5 52.6 31.0 70.6t 54.4z 57.6 42-47 $ A quantity of 100.7 80.2 77.0 101.3 38.8 81.2 95.7 94.6 123.6 95.7 101.5 -t 110.7 52.5 103.6 103.0 109.6 104.8 105.3 111.3 81.2 61.3 80.9 73.6 81.6 68.7 89.9 104.6 110.9 100.8 121.3 95.8 104.0 120.9 64.8 105.7 114.8 121.0 132.4 114.8 125.7 87.8 124.9 72.5 104.6 8 119.3 121.5 115.0 120.9 120.8 101.7 61.5 101.3 82.4 107.6 103.7 99.7 123.4 125.7 119.7 .5 .5 .5 .5 ,251 ,167 1.o 1.o 1.o .2 ,167 .5 ,125 14.8 21.9 -t 15-lot 13-20? NH*CI KF NaCl KBr KCI NazSO. NaOBr C,HaOn C,H,Oe C4H4KNaOs 1.o 1.o 1.0 1 .o 1.o 1.o -3 2.9 2.8 2.3 - 8.2 18.4 5.5 4.1 - 7.9 .5 .5 .5 Amalgamated. t Not constant. corresponding to N a O l l = 1. . t A f t e r some time. hromine was used SMITHWNIAN PHYSICAL TABLES T A B L E 376.-THERMOELECTRIC E F F E C T O F ALLOYS 379 The thermoelectric effect of a number of alloys is given in this table, the authority being Ed. Becquerel. They are relative to lead, and for a mean temperature of 50°C. I n reducing the results from copper as a reference metal, the thermoelectric effect of lead to copper was taken as -1.9. I ' 0 - 0-2 .E Substancr Antimony Cadmium Antimony Cadmium Zinc Antimony Cadmium Bismuth Antimony Zinc Antimony Zinc Bismuth Antimony Cadmium Lead Zinc Antimony Cadmium Zinc Tin z:} Substance 2%; rn b.2.O 2 % gb€ . ; E 4 g.: 4 227 2) 146 1 E} 95 121 137 22r 121 8.1 76 '} 1 f) 1 1 46 Antimony Zinc Tin Antimony Cadmium Zinc Antimony Tellurium Antimony Bismuth Antimony Iron Antimony Magnesium Antimony Lead Bismuth Bismuth Antimony Bismuth Antimony Bismuth Antimony Bismuth Antimony Bismuth Antimony Bismuth Tin Bismuth Selenium Bismuth Zinc Bismuth Arsenic :}-51.4 !}-63.2 !}-68.2 ' ':}-66.9 :> 6o 1;}-24.5 : - 11 '}3 . ':}-46.0 :}-33.4 Bismuth sulfide 1 '> 68.1 T A B L E 377.-THERMOELECTRIC EFFECT A measure of the thermoelectric effect of a circuit of two metals is the electromotive force produced by 1"C difference of tempcrature between the junctions. The thermoelectric Bt, effect varies with the temperature, thus. thermoelectric effect = Q = d E / d t = A where A is the thermoelectric effect at O"C, B is a constant, and t is the mean temperature of the junctions. The neutral point is the temperature at which d E / d t = 0, and its value is - A / B . When a current is caused to flow in a circuit of two metals originally a t a uniform temperature, heat is liberated at one of the junctions and absorbed at the other. The rate of production or liberation of hcat at each junction. or Peltier effect, is given in calories per second, by multiplying the current by the coefficient of the Peltier effect. This coefficient in calories per coulomb = QT/T, in which Q is in volts per degree C, T is the absolute temperature of the junction, and 7 = 4.19. Heat is also liberated or absorbed in each of the metals as the current flows through portions of varying temperature. The rate of production or liberation of heat in each metal, or the Thomson effect, is given in calories per second by multiplying the current by the coefficient of the Thomson effect. This coefficient, in calories per coulomb = BTsIT, in which B is in volts per degree C, T is the mean absolute temperature of the junctions. and 0 is the difference of temperature of the junctions. ( B T ) is Sir W . Thomson's "Specific Heat of Electricity," The algebraic signs are so chosen in the following table that when A is positive, the current flows in the metal considered from the hot junction to the cold. When B is positive, Q increases (algebraically) with the temperature. The values of A , B , and thermoelectric effect in the following table are with rcsprct to lcad as the other metal of the thermoelectric circuit. The thermoelectric effect of a couple composed of two metals, 1 and 2, is given by subtracting the value for 2 from that for 1 ; when this difference is positive, the current flows from the hot junction to the cold in 1. In the following table, A is given in microvolts per degree, B in microvolts per degree per degree, and the neutral point in degrees. The table has been compiled from the results of Becquerel, Matthiessen and Tait; in reducing the results, the electromotive force of the Grove and Daniel1 cells has been taken as 1.95 and 1.07 volts. The value of constantan was reduced from results given in LandoltBornstein's tables. (coiitinued) + SMITHSONIAN PHYSICAL TABLES 380 TABLE 377.-THERMOELECTRIC EFFECT (concluded) A B Microvolts Thermoelectric effect at mean temp. of junctions (microvolts) Aluminum ..................... - .76 Antimony, comm'l pressed wire.. axial ................ equatorial ............ A r g y t a n ...................... -1 1.94 Substance Microvolts +.0039 - 20°C Neutral point Arsenic ....................... Bismuth, comm'l pressed wire.. . ' pure ... ' crystal, axial ......... " equatorial ..... Cadmium ...................... 2.63 fused ................ Calcium ....................... Cobalt ........................ Constantan .................... C o q p r ........................ 1.34 commercial ............ ' galvanoplastic .......... Gallium ....................... Gold .......................... 2.80 Iron .......................... +17.15 '' pianoforte wire ............ " commercial ............... ............... Lead .......................... Magnesium .................... 2.22 Molybdenum ................... Mercury ...................... Nickel ........................ " (-18" t o 175") ........... -21.8 " (250"-300") ............. -83.57 " (above 340") ............. - 3.04 Palladium ..................... - 6.18 Phosphorus (red) .............. Platinum ...................... " (hardened) ........... 2.57 '' (malleable) ........... - .60 wire ................. ' another specimen ...... Platinum-iridium alloys : 85% P t 15% I r ........... 7.90 90% P t 10% Ir ........... 5.90 5% I r ........... 6.15 95% P t Selenium ....................... Silver ......................... 2.12 " (pure hard) .............. " wire .................... Steel .......................... +11.27 Tantalum ...................... T e l l y i u m * p .................. - ...................... - -.0506 - + + 13.56 - 97.0 - 89.0 - 65.0 - 45.0 3.48 - + 22.6 6.0 + + 26.4 - 12.95 - .68 - 50°C .56 -14.47 -12.7 - + 195 - 236 A -B - - + - 22 + +.0101 -.0482 - + 1.52 + .10 + 3.8 - .2 + 3.0 + 16.2 + 17.5 - - + 4.75 + 2.45 + 8.9 -19.3 1.81 3.30 +14.74 +12.10 9.10 - 62 + - 143 + [- + 356 2771 --.0094 - + .oooo + -.0506 +.2384 -.0506 -.0355 -.0074 -.0109 + + + + + + 2.03 5.9 .413 - .oo + .oo + 1.75 - 3.30 -15.50 -24.33 - + 236 [- - - 22.8 - 6.9 29.9 2.42 - .818 - - .F - - 7.96 2.20 - 1.15 .94 - 2.14 4311 174 + + 347 - 55 -12741 444 -11181 - 144 + + + + + + -.0325 +.0147 +.0062 -.0133 .0055 + ........................... ........................... Tungsten ...................... Zinc .......................... I' Thallium ...................... Tin (commercial) .............. a .................. . pure pressed.. ............. - .43 2.32 - - 2.6 +500. +160. + 8.03 + 5.63 + 6.26 +807. + 2.41 + 3.00 + 10.62 . 8 + 8.21 + 5.23 + 6.42 + 2.86 + 2.18 - + - +.0055 f.0238 - - + - + + - + .33 2.0 2.79 3.7 .I .33 - .16 3.51 - + 9.65 - 347 - + + Electrical conductivity of Tea = 0.04, Tea = 1.7 emu. SMITHSONIAN PHYSICAL TABLES 38 1 T A B L E 378.-THERMAL E L E C T R O M O T I V E FORCE O F M E T A L S A N D A L L O Y S VERSUS P L A T I N U M (millivolts) indicates that the current flows from the 0" One junction is supposed to be at 0°C; junction into the platinum. The rhodium and iridium were rolled, the other metals drawn. Temperature, "C Au + -185 - 80 +loo +200 +300 +400 +SO0 +600 +700 +800 +900 +lo00 +1100 +(1300) +(1500) - .15 - .16 - .31 - .30 .74 .72 +1.7 +1.8 +3.0 +3.0 +4.5 +4.5 +6.2 +6.1 +8.2 +7.9 +9.9 +10.6 +12.0 +13.2 +14.3 +16.0 -+16.8 -- Ag 90%Pt+ 100,hPd - .ll + + - .09 + .26 .62 +1.0 +1.5 +1.9 +2.4 +2.9 +3.4 +3.8 +4.3 +4.8 + + .24 + .77 + .15 + .39 - .19 - .56 - .31 - .37 - .35 1WOPt+ 90"/uPd Pd 90%Pt+ 90070 P t f 10C/ORu 10%Rh - .18 +1.2 +2.1 +3.1 +4.2 + .12 + .61 -- - - - - -1.20 -2.0 -2.8 -3.8 -4.9 -6.3 -7.9 -9.6 -11.5 -13.5 - - .53 - .28 - .24 - - .39 - .32 - .31 -+ .73 + .65 + .65 - +1.6 +1.5 +1.5 +2.6 +3.6 +4.6 +5.7 +6.9 +8.0 Ir Rh -- - +2.3 +3.2 +4.1 +5.1 +6.2 +7.2 +8.3 +9.5 +10.6 +13.1 +15.6 +9.2 +10.4 +11.6 +14.2 +16.9 +2.5 +3.6 +4.8 +6.1 +7.6 -9.1 f10.8 +12.6 +14.5 +18.6 +23.1 +2.6 +3.7 +5.1 +6.5 +8.1 +9.9 +11.7 +13.7 +15.8 +20.4 +25.6 T A B L E 379.-THERMOELECTRIC PROPERTIES A T L O W TEMPERATURES"' Thermoelectric emf per "K against silver alloy "C cu Ag Au -255 -240 -220 -200 -180 -160 -140 -120 -100 - 80 - 60 - 40 - 20 0 20 +.07 .45 .90 -.lo +.37 .39 .44 .20 -1.20 - .05 .24 .30 .30 .33 .3f .40 .44 + 47 . .. .51 .55 .58 .53 .56 .21 .22 + .62 .65 2.10 3.40 3.48 2.14 .54 -1.06 -2.52 -3.92 -5.27 -6.52 -7.80 -9.05 -10.32 -11.6 + .75 Pd Pt Fe Pb +1.54 3.60 5.24 5.40 4.36 3.02 1.72 -1.76 -2.80 -3.80 -4.72 -5.62 -6.56 - .70 .so +.05 1.40 4.80 8.45 11.5 14.0 15.8 16.9 17.5 17.5 17.3 16.9 16.2 15.8 15.3 -1.06 -1.19 -1.25 -1.29 -1.33 -1.42 -1.54 -1.67 -1.79 -1.92 -2.05 -2.17 -2.29 -2.42 -2.54 11 ' Borelius, Keesom, Johansson, Linde, Com. Phys. Lab. Leiden, No. 206, 1930. T A B L E 380.-PELTIER Temperature 00 E F F E C T , FE-CONSTANTAN, NI-CU, 0" -560°C 20' 130" 240' Fe-Constantan NiCu . . . . . . . . 3.1 ............ .... 1.92 320" 560°C 3.6 2.15 4.5 2.45 6.2 8.2 1.91 12.5 2.38 2.06 SMITHWNIAN PHYSICAL TABLES 382 "K T A B L E 381.-THOMSON cu E F F E C T IiN MICROVOLTS P E R DEGREE Pa Pt Fe Ni co AK Au 20 25 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 200 220 240 260 280 300 4-.59 1.04 1.22 1.03 .67 .18 - .29 - .46 - .48 - .45 - .37 - .26 - .13 .02 .17 .31 .46 .59 .79 .96 1.10 1.24 1.38 +1.52 + $1.40 1.23 .85 .24 - .02 - .17 - .24 - .25 - .17 - .03 .12 .25 .35 .44 .52 +2.S3 2.09 1.58 .88 .45 .19 .07 + .17 .32 .45 .56 .75 .83 .9 1 .99 1.06 1.19 1.31 1.43 1.54 1.66 +1.77 .05 .66 .59 .66 .72 .84 .96 1.08 1.20 1.32 +1.44 +1.9 2.6 3.1 3.2 2.5 1.0 -1.5 -4.6 -6.6 -7.8 -8.7 -9.3 -9.7 -10.1 -10.3 -10.6 -10.9 -11.2 -12.1 -13.3 -14 6 -15.8 -17.0 -18.2 f3.2 3.6 3.9 3.8 2.7 1.o -1.1 -3.3 -5.1 -6.5 -7.5 -8.0 -8.2 -8.2 -8.3 -8.4 -8.5 -8.7 -9.1 -9.8 -10.6 -11.4 -12.3 -13.2 $1.3 2.7 4.1 6.7 9.0 10.8 11.9 12.6 12.9 13.0 13.0 12.8 12.2 11.0 8.9 6.1 2.6 - .2 -3.5 -4.5 -4.8 -5.2 -5 6 -5.9 -4 5 -5.4 -5.0 -4.5 -4.1 -4.0 -4.0 -4.5 -5.3 -6.4 -7.4 -8.3 -9.0 -9.7 -10.3 -10.9 -12.1 -13.3 -14.5 -15.7 ... ... ... ... - .2 - .3 - .8 -2.0 -3.7 -5.5 -7.0 -8.4 -9.8 -11.1 -12.4 -13.5 -14.6 -15.7 -16.7 -17.6 -19.6 -21.5 -23.4 -25.4 ... ... ... ... -.04 -.06 -.09 -.12 -.15 -.18 -20 -.23 -26 -29 -.32 -.34 -.37 -.40 -.42 -.46 -.49 -9 -274 ... ... .00 Pb -55 -.57 T A B L E 382.-T H E RM 0 E L E C T R I C E F F E C T S ; P R ESSU R E E F F E C T S The following values of the thermoelectric effects under various pressures are taken from Bridgman. A positive emf means that the current at the hot junction flows from the uncompressed to the compressed metal. The cold junction is always at 0°C. The last two columns give the constants in the equation E =thermoelectric force aqainst lead (0" to 100°C) = ( A t Bt') X lo-" volts; a t atmospheric pressure, a positive emf meaning that the current flows from lead to the metal under consideration at the hot junction. + Thermal emf, volts X lo9 Pressure, kg/cm* 2000 4000 8000 12,000 Temperature, I "C 50" 1000 20" 185,000 452,000 710,000 14,400 38,500 87,400 8,780 23,750 52,460 6,680 19,180 45,560 6,750 17,200 35,470 5,090 12,970 26,520 3,880 11,030 21,570 7,050 15,140 2,700 5,140 11,440 1,880 4,950 10,560 +1,900 7,680 220 -990 281 6,330 +880 5.760 2,627 +990 1,616 3,546 +596 1,962 312 -68 833 5 62 +146 +390 -182 +lo -719 -1,314 -308 -648 -1,296 -259 -352 -937 -2,061 Formula coefficients Metal Bi .......... Zn . . . . . . 50" 100' 50' .... T .......... I Cd . . . . . . . . . . Constantan . . Pd . . . . . . . . . . Pt . . . . . . . . . . w .. . . . . . . ., Ni Ag Fe Pb Au ..__...... . . . . .. . . . .......... . . . . . . .... . . . ... . . . cu .. . . .. . ,. A1 . . . . . . . . . . Mo . . . . . . . . . Sn . . . . . . . . . . Manganin MK ......... c o . .. 100" 185,000 28500 20:290 14,380 11,810 8,800 7,310 4,990 3,400 3,720 3,250 2,120 2,051 1,216 294 278 -452 -362 --692 ... . ...... +ins 50" 255,000 26100 17:170 10,960 11,530 8,630 7,370 4,690 3,230 3,350 5,300 1,860 1,791 1,124 32 375 +70 -489 --395 -630 1000 425,000 58,100 37,630 28,740 23,790 17,690 14,350 10.120 7,190 7,190 5,820 4,210 3,974 2,420 929 555 +292 -894 -791 -1,360 ' A -74.42 +3.047 +1.659 +12.002 -34.76 -5.496 -3.092 +1.594 -17.61 +2.556 +16.18 B f.0160 --.00495 -.OO 134' +.1619 --.0397 -.01760 -.01334 f.01705 -.0178 +.00432b -.0089b - - +2.899 +2.777 -.416 +5.892 +.230 +1.366 -.095 -17.32 +.00467e f.00483 +.00008d +.02 1670 --.00067 +.000414f +.00004 -.0390 a, --.0s56ta; b, -.0d36ta, annealed ingot iron; c, -.0a166ta; d. -.0,1t8; e. -.0,25ts; f , -.04112t8 SMITHSONIAN PHYSICAL TABLES T A B L E 383.-PELTIER A N D T H O M S O N H E A T S ; PRESSURE E F F E C T S 383 The following data indicate the magnitude of the effect of pressure on the Peltier and Thomson heats. They refer to the same samples as for the last table. The Peltier heat is considered positive if heat is absorbed by the positive current from the surroundings on flowing from uncompressed to compressed metal. A positive dZE/dtzmeans a larger Thomson heat in the compressed metal, and the Thomson heat is itself considered positive if heat is absorbed by the positive current in flowing from cold to hot metal. Same reference as footnote 141, and notes as for preceding table. 1W x Joules/coulomb Pressure kg/cmP Peltier heat, Thomson heat 108 X J X coulomb-; 'C-1 Pressure kg/cm* 6000 I 12,000 Temperature "C 6000 12,000 Temperature "C 00 50' 1000 0' 50" Metal Bi - +25W +2810 +lo70 +I210 Zn 4-140 3.190 +98 +190 +278 TI +95 +124 +I12 4-17] +66 Cd +71 4-118 +81 4-148 +19 Constantan 4-46 4-57 +70 4-90 f114 Pd .......... +35 4-43 +52 +68 +86 Pt +45 +76 +23 +37 4-35 w .......... 4-17 4-25 +32 +36 +49 Ni .......... 3-11 4-17 +23 +24 +37 Ag +34 Fe -38 +38 Pb .......... 4-10 +16 4-14 +20 A u ......... 4-10 +14 +13 +18 c u ......... 4-4 +6 A1 .......... Mo Sn Manganin ... -2 -2 -2 -4 -4 Mg -16 -a1 -35 -42 -18 co -23 -33 -44 -46 -67 1000 .......... .......... .......... .......... .. .......... ......... .......... - 0" +llSO +lo9 +S 50" +650 +48 100' $412 4-229 4-221 +I40 +lo3 4-65 +6S $ : ! +44 +36 +25 +so +la ' -$ +-'6 -% '+"+ 9" +8 4-7 +6 +9 4-7 +8 +4 +79 +2 +28 +74 +6 +56 +26 +63 +6 +30 +4 +SS +6 +4 4-0 +5 +6 -121 $10 +5 50" 10 0' -405 +133 +220 +63 +SO +lo5 +92 4-93 f13 +14 4-17 +9 +8 +17 +59 +14 +20 +15 4-10 +16 +lo 4-7 +8 -347 +lZO -194 +20 +6 +8 +6 4-7 +6 0' -520 +63 +79 ......... .......... ......... .......... 2: +2 -4 +2 4 8 +6 +; +A -14 -11 -1 +o" +29 +o" -11 +2 -2 -5 +A +; -28 -90 -10 -20 -24 T A B L E 384.-THERMAL E L E C T R O M O T I V E FORCE O F C A D M I U M VERSUS P L A T 1NUM Temperature versus emf "C 0 25 50 75 100 +.171 .378 620 .898 .ooo mv "C mv "C mv 125 150 175 200 225 1.211 1.559 1.940 2.351 2.790 250 275 300 315 3.255 3.740 4.238 4.539 T A B L E 385.-PELTIER EFFECT The coefficient of Peltier effect mav be calculated from the constants A and R of Table 377, as there shown. With Q (see Table 377) in microvolts per "C and T = absolute temperature ( K ) , the coefficient of Peltier effect = - cal per coulomb =O.O0086 QT cal QT 42 per ampere-hour = QT/1000 millivolts (= millijoules per coulomb). Experimental results, expressed in slightly different units are here given. The figures are for the heat production at a junction of copper and the metal named in calories per ampere-hour. The current flowing from copper to the metal named, a positive sign indicates a warming of the junction. Calories per ampere-hour Sb. - Sb commercial t Bi pure - - Bit - Cd German silver -.62 .46 - Fe Ni Pt Ag Zn -3.61 2.5 4.36 .32 -.41 -.58 .39 13.02 $8 19.1 25.8 2.47 - - - *Becquerel's antimony is 806 parts Sb+406 arts Z n + 121 parts Bi. t Becquerel's bismuth i s 10 parts Bi 1 part gb. + SMITHSONIAN PHYSICAL TABLES 384 TABLE 386.-RESISTIVITY OF METALS AND SOME ALLOYS The resistivities are the values of p in the equation R = pl/s, where R is the resistance in microhms of a length I cm of uniform cross section s cmz. The temperature coefficient is a, in the formula Rt = R.[1 a,(t - t , ) ] . The information of column 2 does not necessarily apply to the temperature coefficient. + Tempera- Temperature coefficient Advance ........... see constantan Aluminum ......... -......... c.p. Substance Remarks tpe C Microhmcm -18" 25 100 500 t* __ +.0039 +.0034 +.0040 +.0050 +.0036 - a, ' ......... 20 -189 -100 ' ......... AntiFony .......... -_ __ .......... .......... liquid Arsenic ............ __ Beryllium ......... __ Bisrffuth . . . . . . . . . . . __ __ ........... Brass ............. __ Cadmium .......... drawn .......... .......... .......... liquid Calcium ........... 99.57 pure Calido ............. see nichrome Cesium ............ -__ ............ ' ............ ' ............ liquid } solid Chromium ......... __ Climax ............ __ " " ......... 0 $100 400 -190 n +860 0 20 18 100 20 -160 18 100 318 20 2.828 .64 1.53 2.62 3.86 8.0 39.1 10.5 120 35 10.1 119.0 160.2 7 __ __ __ -_ +.004 __ 20 20 +.W2 +.0038 +.0036 - _- -187 0 27 30 0 20 20 20 -- __ ........ __ ........ __ ........ __ ........ C o y e r ............ annealed ............ hard-drawn ' ............ electrolytic ............ . . . . . . . . . . . . . pure . . . . . . . . . . . . . very pure, ann'ld Eureka ............ see constantan _Excello ............ Gallium ........... __ German silver ...... 18% Ni Germanium ........ __ Gold .............. 99.9 pure __ .............. .............. pure, drawn . . . . . . . . . . . . . . . . 99.9 pure Ia Ia .............. see constantan Ideal ................ Indium ............ Iridium ............ __ ............ __ ............ Iron ............... 99.98% pure ' ............... pure, soft ............... ............... " " " " " " " Cobalt ............. 99.8 pure Comfantan ........ 60% Cu. 40% Ni 2.72 7.54 9.82 34.1 4.59 5.25 19 22.2 36.6 13 87 9.7 49 __ -__ __ 20 12 25 +.0007 __ __ 20 20 -206 +205 400 20 20 0 20 0 -183 0 20 194.5 0 1.724 1.77 .I44 2.92 4.10 1.692 92 53 33 89000. .68 2.22 2.44 3.77 2 " 1000 100 400 20 - -.000033 -.000020 +.WOO27 +.00393 +.00382 +.0038 .0042 +.0062 - +.000002 +.oooOO8 + - 20 " +.00016 +.0004 - 500 1000 20 100 an;'ld -186 -205.3 - 78 0 +l2 0 8.37 1.92 6.10 8.3 10 __ __ 20 25 100 0 ,652 5.32 8.85 +.0050 +.OM2 +.0052 +.0068 lntinued) SMITHWNIAN PHYSICAL TABLES T A B L E 386.-RESISTIV I T Y O F M ETALLS AND SOME ALLOYS (continued) Temperatye 385 Substance 1r:n ............... pure, ............ 'I Remarks soft " " Le;d _........... ... ........... ... cs!d pre:sed ' ........... ... ........... ........... ... __ ........... ... solid Lithium ........ ' ........ ... ........ ... ........ ... liquid __ Magnesium ..... ... ' ..... ... free from ' 1' ............ ... ............ ............ " electrolytic " ..... ... ........ ..... ... " " " " I.' < : t' ,' pure " 'I Manganese Manganin 'I .. ... ' " 1' " Meryry ' ' ' " ........... ........... ........... ........... ........... ........... ........... ........... ........... ........... ........... ......... .. ... ......... ......... ......... ...... ... ..... ... _- 196.1 400 0 100 20 -183 - 78 0 90.4 196.1 318 -187 0 99.3 230 20 -183 - 78 0 -+98.5 400 + 98.5 C Microhmcm + 17.8 21.5 43.3 10.0 14.41 22 6.02 14.1 19.8 28 36.9 94 1.34 8.55 12.7 45.2 4.6 ~~ 500 1000 n +.0147 +.0050 - Temperature coefficient I - __ _+.004 +.no38 _- 84 Cu, 12 Mn, 4 Ni 20 -- 11.9 5.02 44 20 0 25 100 500 600 12 25 100 250 475 500 20 0 Rt = Ro(1 .00089t .ooOoOl t') +.0100 __ solid _20 -183.5 -102.9 - 50.3 - 39.2 - 36.1 0 50 100 200. 350 0 20 20 20 20 -182.5 - 78.2 0 94.9 _95.783 6.97 15.04 21.3 25.5 80.6 ' --.000052 --.OOOO00 -.OOoll +.00089 +.OW88 + + __ _- liquid ' Molybdenum ....... very pure __ ....... 135.5 5.14 Monel metal ....... Nichrome .......... Nickel ............. ............. very pure ............. pure ............. ............. ............. __ ............. __ Osmium ........... _Pall+um ......... ......... very pure 'I __ -__ __ -42 100 7.8 7.236 1.44 4.31 6.93 11.1 9.5 11 2.78 7.17 10.21 13.79 9.83 2.44 6.87 10.96 14.85 26 __ __ 25 100 1000 20 20 20 0 25 100 500 1000 20 0 +.0033 +.0034 ,0048 +.0020 +.OW4 +.006 + - + Platinum " ......... ......... ......... .......... .......... wire .......... .......... .......... .......... I' ' I " " 'I 'I 20 20 -183 - 78 0 98.5 0 -203.1 - 97.5 0 100 400 (continued) - +.0062 +.0043 ,0043 +.0030 +.0037 -- +.0033 +.0035 --- +.003 +.0037 SMITHSONIAN PHYSICAL TABLES 386 TABLE 386.-RESISTIVITY O F METALS AND SOME ALLOYS (continued) Temperatye Temperature coefficient Microhmcm Tantalum .......... Tellurium* ........ -Thallium .......... pure " " " ............ ............ liquid Stzel .............. E. B.B. .............. B.B. .............. Siemens-Martin .............. manganese .............. 35%Ni, "invar." .............. piano wire .............. terffp. glass, hard .............. , yellow .............. , blue .............. , soft Strontium ......... " 'I -......... -......... ......... R h o F m .......... --.......... _.......... ' .......... -Rub$lium .......... sofJd .......... ' .......... ' .......... liquid Silicium ........... -Silver ............. 99.98 pure ............. e1ect;olytic ............. ............. ............. ' ............. ............. Sodium ............ so!id ............ ............ Potassium " " " " " " " " " Substance Remarks - 75 C '' " " " " " " " " Tin " ............... .......... .......... .......... ' .......... .......... ' .......... .......... Z i y ............... trace ............... ............... ............... ............... ............... liquid Titanium Tunpen 'I .......... .......... ............... ............... ............... ............... .......... ' -- -- -186 - 78.3 0 10 -190 0 35 40 20 18 -183 - 78 0 98.15 192.1 400 -180 - 75 0 55 116 20 20 20 20 20 0 0 0 0 0 20 20 19.6 -183 - 78 0 98.5 20 -184 - 78 0 91.45 0 55 4 6.1 8.4 .70 3.09 5.11 6.60 2.5 11.6 13.4 19.6 582 20 25 100 -+.0038 +.0030 +.0036 ,0044 '6 " " 'I 'I " 1.629 .390 1.021 1.468 2.062 2.608 3.77 1.o 2.8 4.3 5.4 10.2 10.4 11.9 18 70 81 11.8 45.7 27 20.5 15.9 24.8 15.5 200,000 4.08 11.8 17.60 24.7 11.5 3.40 8.8 13 i8.z 55 20 5.51 727 25.3 1227 41.4 1727 59.4 2727 98.9 3227 118 -183 1.62 3.34 - 78 0 5.75 92.45 8 10.37 191.5 440 37.2 500 + ?? y c$. ?' " " '1 " " 'I " I' 'I +.05 +.04 +.03 +.001 - 0 see col. 2 '1 " " +.0032 +.0016 +.0033 +.0031 - - 18 500 1000 * See note to Table 377. SMITHSONIAN PHYSICAL TABLES 387 T A B L E 386.-RESISTIVITY O F M E T A L S A N D S O M E A L L O Y S (concluded) Resistance temperature coefficient for a number of metals and alloys of high purity. (R,m-Rfl)/ 100Rfl Ni . . . . . . . . . . . . . Zn ~. ..... . .. ... Cd . . . . . . . . . . . . P t . . . .. . ... . . .. Rh . . . . . . . . . . . . .00667 .00419 .00423 ,003925 .00436 95 Pt- 5 .. - . 90 Pt-10 80 Pt-20 60 Pt-40 40 Pt-60 20 Pt-80 R.. - h . Rh Rh Rh Rh Rh .00215 ,00169 .00140 ,00144 ,00194 .00260 T A B L E 387.-SOME E L E M E N T S A R R A N G E D I N O R D ER O F I N C R E A S I N G R E S I S T I V I T Y (ohm-cmxlO-a, 20°C) Ag Au A1 Cr Ti Na Ca Mg Rh W cu 1.468 1.59 2.22 2.6 2.6 3.2 4.3 4.3 4.35 4.69 5 Mn Mo Zn Ir I< Ni Cd In Li Fe co (y& 6.10 6.1 6.93 7.04 8.37 8.55 8.8 9 5 2 Pd Pt Rh Sn Ta TI Cs Ph Sr As Sb 10.21 10.96 13 13 14.6 17.6 19 20.4 (23.5) 35 39 Ga 2 53 56 94.07 110 Graphite 8x10' Carbon 3x10' Te 2X10' P 10" B 8X10" Se 10'" S 1017 0s T A B L E 388.-THERMAL E L E C T R O M O T I V E F ORC E O F PLA TllN U M-R H OD IU M ALLOYS VERSUS P L A T I N U M emf (mv) Percent rhodium T:mp. C 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 +.I0 20 29 .39 .48 .58 .67 .76 .85 .94 1.03 1.13 .oo .5 1.0 +.I8 .37 .57 .76 .94 1.12 1.30 1.48 1.66 1.84 2.02 2.20 .oo 5.0 +.54 1.16 1.82 2.49 3.17 3.86 4.55 5.25 5.96 6.68 7.42 8.16 .oo 10.0 +.64 1.43 2.32 3.25 4.22 5.22 6.26 7.33 8.43 9.57 10.74 11.93 .oo 20.0 +.63 1.44 2.40 3.47 4.63 5.87 7.20 8.59 10.06 11.58 13.17 14.84 .oo 40.0 80.0 .00 +.65 1.52 2.55 3.70 4.97 6.36 7.85 9.45 11.16 12.98 14.90 16.91 +.62 1.49 2.55 3.77 5.12 6.60 8.20 9.92 11.76 13.73 15.81 17.99 .oo 100.0 +.70 1.61 2.68 3.91 5.28 6.77 8.40 10.16 12.04 14.05 16 18 18.42 .oo T A B L E 389.-EFFECT O F T E N S I O N ON T H E RESISTANCE OF M E T A L S Li Recip. Young's mod. X 10' . . . . . . 20 Poisson ratio . . . . . . .42 Tens. coef. spec. resist. x 10" . . . . .+11 Ca Sr Sb Bi Manganin Co 4.75 .30 7.5 .36 -21.2 1.25 .30 ? +3.0 4.2 .37 -3.65 .72 .33 -.60 .5 .30 +.I9 +.8 SMITHSONIAN PHYSICAL TABLES 388 T A B L E 390.-VARIATION O F THE E L E C T R I C A L R E S I S T A N C E W I T H PR ESSU R E FOR T W O T E M P E R A T U R E S O F A N U M B E R O F M E T A L S " 2 Copper-AR/R, Pressure kg/cma Silver-AR/R, Gold-AR/R, Iron-AR/R, Lead--AR/R, ~~~~~c .0096 .0186 .0271 .0354 .0434 .0513 ,0094 ,0185 .0271 .0354 .0435 .05 14 .0174 .0338 .0492 .0637 .0774 0904 ,0176 .0311 .0497 .0644 .0784 .0916 .015 1 ,0293 .0429 .0559 ,0684 ,0806 .0154 ,0299 .0437 .0570 ,0698 ,0824 ,0121 .0234 ,0341 ,0444 .0542 .0637 ,0118 .0232 .0341 .0447 ,0548 ,0646 ,0686 ,1266 ,1770 ,2214 ,2611 ,2959 ,0691 .I277 .I791 ,2242 ,2643 2998 5,000 10,000 15,000 20,000 25,000 30,000 'WBridgman, Proc. Amer. Acad. Arts and Sci., vol. 72, p. 174, 1938. T A B L E 391.-RELATIVE E L E C T R I C A L R E S I S T A N C E W I T H PR ESSU R E FOR T W O TEMPERATURES OF A NUMBER OF M E T A L S * Zinc Lithium 'R/R. R/R.' Pressure (0. 30 ) (0, 75 ) kg/cm2 30°C 75°C Calcium R/R(O,300) 30 Strontium Barium R / R ( @ , 30") 0 2.500 $000 7,500 10,OOO 12,500 15,000 17,500 20,000 22.500 1.0175 1.0354 1.0539 1.0727 1.0920 1.1117 1.1318 1.1524 1.1735 25:OOO 1.1919 27:SOO 1.2169 30,000 1.2394 -_ 1.0172 1.0351 1.0537 1.0730 1.0928 1.1131 1.1339 1.1553 1.1770 1.1992 1.2221 1.2453 __ c 75 c h R/R(O, 30') Axis 87" to length R/Ro (0, 30 ) to Axis 17" length R/Ro (0,3@1 30°C 75°C Pressure kg/cm2 n Potassium R/R(O, 30') 1.0000 1.0237 1.0490 1.0764 1.1069 1.1407 1.1772 1.2164 1.2582 1.3025 1.3491 1.3983 1.4500 1.1688 1.1922 1.2187 1.2485 1.2816 1.3178 1.3571 1.3998 1.4460 1.4959 1.5485 1.6033 1.6603 1.0000 1.1141 1.2448 1.3922 1.5562 1.7364 1.9333 2.1467 2.3767 2.6273 2.8905 3.1695 3.4665 1.0974 1.2140 1.3451 1.4908 1.6510 1.8258 2.0153 2.2195 2.4377 2.6703 2.9187 3.1805 3.4585 1.0000 .98? ,971 ,967 .970 ,976 ,984 .995 1.008 1.025 1.044 1.066 1.092 1.156 1.130 1.114 1.107 1.106 1.108 1.113 1.123 1.140 1.161 1.184 1.211 1.241 1,0000 .9868 ,9744 ,9638 ,9518 .9416 .9321 ,9233 ,9150 ,9072 ,8998 ,8926 ,8855 1.1627 1.1488 1.1355 1.1228 1.1107 1.0991 1.0880 1.0776 1.0677 1.0582 1.0498 1.0420 _- 1.0000 .9758 ,9525 .9300 ,9081 .8882 ,8686 .8500 ,8321 ,8153 ,7990 .7835 .7687 1.1650 1.1352 1.1062 1.0809 1.0562 1.0325 1.0103 .9890 ,9687 ,9495 .9310 ,9129 .8959 Cesium R/R(O, 30") R/R(O, 30") Sodium 1.nnnn 30" 2,500 5.000 7:500 1o:ooo 12,500 15,000 17.500 2o;ooo 22,500 25,000 27,500 30,000 .664 .491 .378 .303 253 219 .197 .1821 __ __ 750 -_ .615 .467 ,372 ,310 ,269 242 ,224 .216 1.0030 ,807 .812 ,884 1.005 -1.046 1.117 1.260 __ Rubidium R/R(O, 30") .1719 -.1778 __ ___ _- 4.509 1.om0 A529 ,7537 ,6762 ,6171 ,5708 ,5341 SO49 .4813 ,4619 ,4456 ,4324 .4223 1.oo00 .615 ,471 ,407 .371 .354 ,350 ,358 .376 .404 ,447 ,504 .57G For reference, see footnote 142, above. SMITHSONIAN PHYSICAL TABLES T A B L E 392.-THERMAL E L E C T R O M O T I V E FOR C E O F N I C K E L VERSUS P L A T I N U M 389 Temperature versus emf "C 0 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 3 ' 1 -.350 .710 1.ow 1.485 1.880 2.285 2.695 3.105 3.505 3.870 4.255 4.590 4.880 5.110 5.290 .ow mv "C mv "C . mv 400 425 450 475 500 525 .~~ 550 575 600 625 650 675 700 725 750 775 5.450 5.580 .. ~ 5.745 5.960 6.165 6.360 6.585 6.800 7.040 7.290 7.550 7.825 8.105 8.415 8.720 9.030 800 825 9.350 9.675 850 875 900 925 950 975 1000 1025 1050 1075 1100 11.045 11.400 13.625 Nat. Bur. Standardz Journ. Res., vol. 5, p. 1291, 1930. T A B L E 393.-AVERAGE PRESSURE COEFFICIENTS * O F ELECTRICAL R E S I S T A N C E U P T O 7000 kg/cr.z AS A F U N C T I O N O F T E M P E R A T U R E " ' Temperatures Lead . . . . . . . . . . . Magnesium . . . . . . Aluminum . . . . . . . Silver . . . . . . . . . . . Gold . .... . . .. . . Copper . . . . . . . . . Nickel . . . . . . . . . . . Iron . . . . . . . . . . Palladium . . . . . Niobium . . . . . . . . Platinum . . . . . . . . Rhodium . . . . . . . Molybdenum . . . . . Tantalum . . . . . . . Tungsten . . . . . . . . Metal . . -182.0OC -78.4"C 0°C 30°C 75°C . . .. . . . . . -12.76 -5.89 -9.16 -4.09 -3.27t -3.09 -1.88 -2.44 -2.82 - .so -2 31 -2.26 -1.91 -1.17 -1.36 -12.88 -4.49 -4.71 -3.46 -2.97 -2.14 -2.00 -2.27 - 2.32 - .98 -1.97 -1.86 -1.29 -1.42 -1.42 -12.99 -4.39 -4.28 -3.45 -2.94 -1.88 -1.85 -2.34 -2.13 -1.18 -1.93 -1.64$ -1.30 -1.45 -1.37 -9.3 -3.0 -2.6 -1.7 -9.2 -3.0 -2.7 -1.7 144 XI00 13ridgman. P. W., Proc. Anier. .\cad. A r t s and Sci., vol. 67, p. 342, 1932. Maximum pressure 4300. $ On a less pure sample. t T A B L E 394.-RESISTIVITY Pressure, kg/cmz - O F M E R C U R Y A N D MA N GA N IIN U N D E R P R E S S U R E 500 1003 1500 2000 2500 3000 4000 5000 6000 6500 K (p , R(p, * Hg K(p, -75 ') Hg . . .91S6 .9055 25") Hg . . . . 1.OOOO ,9836 . . . . . . . . . . . . 1.0030 ,9854 125") H g . . . 1.0970 1.0770 3930 .9682 .9716 1.0583 .8818 ,9535 .9588 1.0400 ,8714 .9394 .9462 1.0230 .8582 ,9258 .9342 1.0070 3478 .9128 ,9228 ,9908 3268 ,8882 ,9010 .9614 ,8076 ,8652 .8806 ,9342 ,7896 3438 3616 .9086 .7807 3335 ,8527 .8966 This line gives the specific mass resistance at 25" the other lines, the specific volume resistance. T h e use of mercury as ahove has the advantage of bklng perfectly reproducible so that at any time a pressure can be measured without recourse to a fundamental standard. However. a t 0°C mercury freezes a t 7500 kg/cmz. Manganin is suitahle over a much wider ranKe. Over a temperature range 0 to 50°C the pressure resistance relation is linear within %o percent of the change of resistance u p to 13.000 kg/cmz. T h e coefficient varies slightly with the saniple. Gridgmau's samples (German) had values of ( A R / b R " ) x 109 from 2295 to 2325. These a r e instead of -, a s with most of the ahove metals. + SMITHSONIAN PHYSICAL TABLES 390 T A B L E 395.-THERMAL E L E C T R O M O T I V E FORCE O F Z I N C VERSUS P L A T 1N U M 'Temperature versus emf "C mv "C mv "C mv 100 125 .758 1.005 150 175 200 225 250 275 1.276 1.572 1.894 2.240 2.610 3.002 300 325 350 375 400 415 3.417 3.853 4.310 4.786 5.290 5.604 T A B L E 396.-CON DUCT1V l T Y A N D R E S l S T l V l T Y O F M I S C E L L A N E O U S A L L O Y S Temperature coefficients 1 Conductivity in mhos or = y * = yO(l- at ohms-crn =pt =p0(1 + a t ht2). ~ + b t 2 ) and resistivity in microhm - cm YO 10' a X 100 PO Metals and alloys Composition by weight Gold-copper-silver I< " " Invar ............................................. Welding iron .......... 0.05% Cu . . . . . . . . . . . . . . . . . . Woods metal . . . . . . . . . .. 56 Bi, 17 Cd. 14 Pb, 13 S n . . . . Brass ................. Various .................... ' hard drawn . . . . . 70.2 Cu+ +29.8 Zn ......... ' annealed . . . . . . . . ........... German silver .......... Various .................... (60.16 Cu 25.37 Zn 1 " 14.03 Ni .30 Fe with trace of cobalt and manganese Aluminum bronze .................................. Phosphor bronze ................................... Silicium bronze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manganese-copper ...... 30 Mn 70 Cu . . . . . . . . . . . . . Nickel-manganesecopper ............... 3 Ni 24 Mn 73 Cu .... . , f 18.46 Ni 61.63 Cu I Nickelin 19.67 Zn 0.24 F e . 0.19 Co 0.18 Mn J 25.1 Ni 74.41 Cu Patent nickel ............ 0.42 F e 0.23 Zn [ 0.13 Mn trace of cobalt I 53.28 Cu 25.31 Ni Rheotan ............... 16.89 Zn 4.46 Fe 0.37 Mn Rheotan ............... 53 Cu, 25 Ni, 17 Zn, 5 F e . . . . Copper-manganeseiron ................. 91 Cu 7.1 Mn 1.9 F e . . . . Copper-manganeseiron ................. 70.6 Cu 23.2 Mn 6.2 F e . . Cqpper-manganeseiron .................. 69.7 Cu 29.9 Ni 0.3 Fe .. Therlo ................ 85 Cu, 13 Mn, 2 Al .......... Manganin ............. 84 Cu 12 Mn 4 N i ...... Constantan ............ 60 Cu 40 Ni .............. ...... ...... ...... 58.3 Au 66.5 Au 7.4 Au + 16.5 Cu + 15.2 Ag + 15.4 Cu + 18.1 Ag + 78.3 Cu + 14.3 Ag .......... I + + + 7.58 6.83 28.06 1.33 6.25 1.93 12.2-15.6 12.16 14.35 3-5 3.33 7.5-8.5 10-20 574* 529'1 1830t Zoo0 6000 2900 1-2+103 -- __ 360 13.2 14.6 3.6 75 18 52 6.4-8.4 8.2 7.0 20-33 30 12-13 5-10 2.4 100 48 33 34 53 45 20 77 38 46.5 44 49 r 600 _- ............... { \ 1 + + + + + + + + + + + + + + + + + + + + + + + 41 1.oo 2.10 3.01 2.92 1.90 2.24 4.98 1.30 2.60 2.24 2.3 2.04 -40 -30 i 300 190 410 i 1 280 120 22 120 10 6 8 + + + *bX 10" = 924. t b X 10" = 93. b x 10" = 7280. SMITHSONIAN PHYSICAL TABLES T A B L E 397.--ELECTRICAL C O N D U C T I V I T Y O F ALLOYS 31 9 This table shows the conductivity of alloys and the variation of the conductivity with temDerature. The conductivitv is given as C, = CO(1 -at bt'), and the range of tern' perature was from 0 0 to IOO*C. The table is arranged in three groups to show (1) that certain metals when melted together produce a solution which has a conductivity equal to the mean of the conductivities of the comoonents. (2) the behavior of those metals alloyed with others, and (3) the behavior of the metals'alloyed together. - + Part 1 Weight % Volume % SnsPb ........,......... S a C d ............ ..... SnZn ... ............... FbSn . . . . . ... . ... ZnCdl . . ............... SnCd, ................. . CdPb, . . . . . . Alloys of first named C" 10' aX 1 P b X 109 ..... . . . . . . . . .. 77.04 82.41 78.06 64.13 24.76 23.05 7.37 83.96 83.10 77.71 53.41 26.06 23.50 10.57 Part 2 7.57 9% 10.56 6.40 16.16 13.67 5.78 3890 4080 ~~. 3880 3780 3780 3850 3500 8670 11870 8720 8420 8000 9410 7270 Volume % Weight 5% .. .. Tin-g:!d (Sn12Au) . ... . 77.94 (SnaAu) . .. ... 59.54 Tin-coppr . . . ... . ... ... 92.24 . . ... . . . . .. . . 80.58 ............. 12.49 ............. 10.30 . . .. ... . ..... 9.67 . . . . .. .. ..... 4.% " " I' I' Lead-silver (PhoAg) . .. 95.05 Lead-silver (PbAg) . . 48.97 Lead-silver (PbAgr) . 32.44 Alloys of first'named I C" 104 a x 100 94.64 46.90 30.64 90.32 79.54 93.57 83.60 14.91 12.35 11.61 6.02 1.41 96.52 75.51 42.06 29.45 23.61 10.88 5.03 5.60 8.03 13.80 5.20 3.03 7.59 8.05 5.57 6.41 7.64 12.44 39.41 7.81 8.65 13.75 13.70 13.44 29.61 38.09 3630 ____ b X loo 1960 1990 7960 3100 2600 6640 6300 8130 6840 294 1185 304 705 5070 8190 8550 1340 3080 2920 3680 3330 547 666 691 995 2670 3820 3770 1370 " " " " 'I I' ............. 1.15 . . . . . .. . . ... . . . . . . .. ... . .. Zinc-copper . . . . . ... .... . . . . . .. . .... ............ . .. ......... ' Tin-silver '> " " I' 91.30 53.85 36.70 25.00 16.53 8.89 4.06 " " " ............ NoTE.-Barus has pointed out that the temperature variation of platinum alloys containing less than 10% of the other metal can be nearly expressed by an equation y =? -fi:, z where y is the temperature coefficient and x the specific resistance, m and n being constants. If a be the temperature coefficient at 0°C and s the corresponding specific resistance, s(a m ) =n For platinum alloys Barus's experiments gave nt = -.000194 and n = .0378. For steel in = -.U00303 and n = ,0620. Matthiessen's experiments reduced by Barus gave for Gold alloys m = -.000045, n = .00721. Silver m = -.000112, n = .00538. Copper m = -.000386, n = .00055. + :: (cn?tt;?tlled) SMITHSONIAN PHYSICAL TABLES 392 TABLE 397.-ELECTRICAL CONDUCTIVITY O F ALLOYS (concluded) Part 3 L Weight "/o Volume 7% Alloys of first named c .. o Gold-copper Gold-silver 'I I' " 'I '1 " 'I I' 'I " ........... ............ 87.95 ............ 87.95 ............ 64.80 ............ 64.80 ............ 31.33 ............ 31.33 ........... 34.83 ........... 104 a X 108 b X lon 99.23 90.55 98.36 81.66 79.86 79.86 52.08 52.08 19.86 19.86 19.17 .71 19.65 5.05 2.51 23.28 98.35 95.17 77.64 46.67 8.25 1.53 27.93 21.18 10.96 35.42 10.16 13.46 13.61 9.48 9.51 13.69 13.73 12.94 53.02 4.22 11.38 19.96 5.38 56.49 51.93 44.06 47.29 50.65 50.30 1.73 1.26 1.46 24.51 4.62 14.91 3.97 8.12 38.52 2650 749 1090 1140 673 721 885 908 4650 81 793 1160 246 495 531 641 570 7300 208 656 1150 154 7990 6940 6070 5280 4360 8740 7010 1220 103 GEld-coqper ............ 1.52 Platiym-silver ........ 33.33 ' ........ 9.81 ' 864 3320 330 774 1240 324 3450 3250 3030 2870 2750 4120 3490 2970 487 1550 476 1320 516 736 2640 ........ 5.00 Palladium-silver Copper-silver " " " " .......... 94.40 .......... 76.74 .......... 42.75 .......... 7.14 .......... 1.31 13.59 9.80 4.76 ....... .......... 25.00 98.08 Iron-gold " " " " Iron-copper " .............. . . . . . . . . . . . . .40 Phosphorus-copper ..... 2.50 " " .............. .............. . . . . . .95 5.40 2.80 trace .46 . . . 2090 145 1640 989 446 4830 Arsenic-copper ' ......... ......... ......... - SMITHSONIAN PHYSICAL TABLES T A B L E 398.-RESISTIVITIES A T HIGH AND L O W T E M P E R A T U R E S 393 The electrical resistivity ( p , ohm-cm) of good conductors depends greatly on chemical purity, Slight contamination even with metals of lower p may greatly increase p . Solid solutions of good conductors generally have higher p than components. Reverse is true of bad conductors. I n solid state allotropic and crystalline forms greatly modify p . For liquid metals this last cause of variability disappears. The temperature coefficients of pure metals is of the same order as the coefficients of expansion of gases. For temperature resistance ( t , p ) plot at low temperatures the graph is convex toward the axis of t and probably approaches tangency to it. However for extremely low temperatures Onnes finds very sudden and great drops in p, e.g., for mercury, PJ.~K <4 X 1O-'Op0 and for Sn, pJ.m 200,000,000. 2oo.ono. 30.000. m. 30. about 20. 900. 1000. 1100. 1200. 1600. >9X10a 30800. 13600. 7600. 6500. 2300. 190. Diamond 1030"C, p > 107; 1380", 7.5 X 105. T A B L E 399.-SUPERCONDUCTIVITY Metal T"K Metal O F SOME M E T A L S T"K Metal ............... .... .... Ta . . . . . . . . . . . . . . . Nh 9.22 7.2 5.2 4.4 . . . . 4.3 Hg . . . . . . . . . . . . . . 4.15 Sn . . . . . . . . . . . . . . . 3.71 I n . . . . . . . . . . . . . . . 3.38 u ............... 0s T"K Zr . . . . . . . . . . . . . . . Al . . . . . . . . . . . . . . . 1.15 . . . . . . . . . . . . . . . .71 .75 .54* Zn . . . . . . . . . . . . . . .95t Ti . . . . . . . . . . . . . . . .53t Ru . . . . . . . . . . . . . . . .47 Hf . . . . . . . . . . . . . . . .35 s ' Smith Thomas S., Ohio State University, private communication. 1 D a u n t . ' J . G., and Smith. T . S. t Daunt, J . G., and Heer. C. V.. Phys. Rev., vol. 76, pp. 719 and 1324, 1948. T A B L E 400.-SUPERCONDUCTIVITY OF SOME ALLOYS A N D COMPOUNDS"e NhC . . . . . . . TaC ....... Ph-As-Bi .. Ph-Ri-Sh .. P b S n - B i .. 14" 10.1"K 9.2 9.0 8.9 8.5 Ph-As alloy. MoC . . . . . . . NiPh ..... BioTI, . . . . . . ShzTIT . . . . . TaSi ....... 8.4"K 7.7 7.2 6.5 5.5 PhS ....... Hg5T17. . . . . ZrR . . . . . . . WC . . . . . . . MozC . . . . . . 4.1"K 3.8 2.82 2.8 2.4 4.2 W,C . . . . . . . AulBi . . . . . . CuS ....... T i N ....... V N ........ T i c ........ 2.05"K 1.84 1.6 1.4 1.3 1.1 Smith, G . I f . . an(l LVilhelm. J. 0.. Rev. hlod. Phys., vol. 7 , p. 240, 1935 SMITHSONIAN PHYSICAL TABLES 395 T A B L E 401.-VOLUME A N D SURFACE RESISTANCE OF SOLID DIELECTRICS The resistance between two conductors insulated by a solid dielectric depends both upon the surface resistance and the volume resistance of the insulator. T h e volume resistivity, p, is the resistance betweeii two opposite faces of a centimeter cube. The surface resistivity, u, is the resistance between two opposite edges of a centimeter square of the surface. The surface resistivity usually varies through a wide range with the humidity. Material u ; megohms 50% humidity u ; megohms 70% humidity Amber . ....... ... . ...... .... . .... Beeswax, yellow . . . . . . . . . . . . . . . . . . Celluloid . . . . . . . . . . . . . . . . . . . . . . . . . Fiber. red ........................ u : megohms 9 0 1 humidity P Megohm-cm 6x10' 6x10" 5X 10: 2x10 Sulfur . . . . . . . . . . Wood, paraffined mahogany . . . . . . . . 4x10' 2 x 10' 6x10' 2x104 3X103 6% 10 4X103 1x10' 11 3 x0 3><10* 2x10' 4x10" 7x10' 7X103 2X1O3 3x10' 6x10' 3x10' 3x10 4x10' 5X 10' 1x10~ 5x10' 2x103 2X1O2 2x10 1x103 2 x lo= 3x10 5x10" 2x10 8x10' 6x10'' 5X'02 2x10 2x10' 9x10' 7 x 103 1x10 1x10' 11 3 x0 5x10" 2x10~ 2 x 10' 5x10' 2x10. 8x10' 1x1012 2x102 2x100 1x10' 2x1011 1x10'0 3x10' 5x10'0 8x10' 1x10'0 1x102 1x1011 4><10' 5 x T A B L E 4OP.-ELECTRICAL RESISTIVITY OF SOME OXIDES AND MISCELLANEOUS MINERALS * Material Resistivity ohm-cm Graphite, commercial electrodes (density = 1.5) ,001-,0013 Hematite, Fez03,m-ineral. . .35-.7 Iron. metallic. meteoric . . . 2.4-3.2X6-'? Rock salt, pure .... . . .. .. 10"-lo' impure ....... 10' * F o r reference, see footnote 45, p. 136. Sulfur . . . . . . . . . . . . . . . . .>lo" PbOz, synthetic . . . . . . . . . . .OOOO92 MnOl, synthetic .... ...... 6 W20s . . . . . . . . . . . . . . . . . . . ,00045 wo, . . . . . . . . . . . . . . . . . . . 2x106 Material Resistivity ohm-cm T A B L E 403.-ELECTRICAL RESISTIVITY O F ROCKS A N D SOILS * Sedimentary rocks Resistivity ohm-cm Granite . . . . . . . . . . . . . . . . . . . . Lava flow (basic) . . . . . . . . . . . Lava, fresh . .... . ... . ..... .. Quartz vein, massive . . . . . . . Igneous rocks Resistivity ohm-cm . 107-1 0 9 108-10' 0 3 x 106-1' >I00 Resistivity ohm-cm Limestone . . . . . . . . . . . . . . . . . . Limestone, Cambrian . . . . . . . Sandstone, eastern . . . . . . . . . . Sandstone . . . . . . . . . . . . . . . . . . Limestone . . . . . . . . . . . . . . . . . . 10' 104-106 ' 3 X 10x-10 1O6 106 Resistivity ohm-cm Marble, white ... ........... Marble . . . . . . . . . . . . . . . . . . .. Marble, yellow . . . . . . . . . . . . . Schist, mica . ... ... ... . . ... . Shale, Nonesuch . . . . . . . . . . . Shale, bed .............. ... Metamorphic rocks 1O'O 4x10' . loio 107 104 106 Clay, blue . ... ... .......... Clayey earth . .............. Clay, fire ... . .... .... ... . .. Gravel . , . . . . .. . . .. . , ,. , . .. Sand, dry . ... .... ... ....... Sand, moist ... ............. Unconsolidated materials 2x105 2x10' 10'-4X 10' 1O6 1O6-l0' 105-100 *For reference, see footnote 4 5 , p. 136. SMITHSONIAN PHYSICAL TABLES 396 T A B L E 404.-RESISTIVITY OF SOILS A N D SEA W A T E R M E A S U R E D W I T H HIGH-FREQUENCY ALTERNATING CURRENT * Soil, very dry .. 1 to 10,000 Topsoil, dry .... 37,000 Material Frequency Resistivity kilocvcles/sec ohm/cm Material Frequency Resistivity kilocycles/sec ohm/cm 10' 7,000 Clay, dry ....... Chalk (moisture, 24%) Sea water 37,000 100 1.200 10:660 100 1,200 10,000 60,000 33,000 22.000 141000 21 21 16.5 Loam, dark (moisture, 60%) 100 1,200 10,Ooo 2,600 2,300 1,500 For reference, see footnote 45, p. 136. T A B L E 405.-ELECTRICAL Material RESISTIVITY OF NATURAL WATERS Resistivity ohm-cm Material * Resistivity ohm-cm Very fresh distilled waters ...... 2x10' Mine waters ................... 500 For reference. see footnote 15, p. 136. Potable ground waters ......... 108-106 Surface waters ................ 10' T A B L E 406.-RESISTIVITY OF S O M E GLASSES A T T H R E E TEM PE RATURES Log 10 Volume resistivity (ohm-cm) / - Potash soda lead ...... Lamp tubing Soda lime ............ Lamp bulbs Potash soda lead ...... Lamp tubing H a r d Lime ........... Cooking utensils Borosilicate ........... Kovar sealing Borosilicate ........... Low loss electrical Borosilicate ........... Baking ware Pyrex ................ General Vycor ................ Low expansion ultraviolet transmission Fused quartz .......... Glass Principal use Density 25°C 250°C 350°C 2.85 2.47 3.05 2.53 2.28 2.13 2.24 2.23 2.18 2.20 17.+ 12.4 17.+ 17.+ 17. 17.+ 15. 15. 17.+ 8.9 6.4 10.1 11.4 9.2 11.2 8.2 8.1 11.2 7.0 5.1 8.0 9.4 7.4 9.1 6.7 6.6 9.2 10.48 1 Corning Glass Co. publication, Properties of selected commercial glasses, 1949. General Electric " Co. publication, Fused quartz, 1947. SMITHSONIAN PHYSICAL TABLES