Table 382. — ELECTRICAL EQUIVALENTS. 



311 



Abbreviations: int'n'l, international; emu, electromagnetic units; esu, electrostatic units; 

 cgs, centimeter-gram-second units. (Taken from Circular 60 of U. S. Bureau of Standards, 

 1916, Electric Units and Standards.) 



Resistance: 



I international ohm = 

 1.00052 absolute ohms 

 1. 0001 int'n'l ohms (France, before 191 1) 

 1. 00016 Board of Trade units (England, 



1903) 

 1. 01358 B. A. units 

 1.00283 "legal ohms" of 1884 

 1 . 06300 Siemens units 



I absolute ohm = 



0. 99948 int'n'l ohms 

 I " practical " emu 

 10^ cgs emu 



1 . II 24 X io~^'^ cgs esu 



Current: 



I international ampere = 



0. 99991 absolute ampere 



1 . 00084 int'n'l amperes (U. S. before 191 1) 

 1. 00130 int'n'l amperes (England, before 



1906) 

 1. 00106 int'n'l amperes (England, 1906 



08) 

 i.oooio int'n'l amperes (England, 1909- 



10) 

 1.00032 int'n'l amperes (Germany, before 



1911) 



1 . ooo2int'n'l amperes (France,before 1911) 



I absolute ampere = 



I 00009 int'n'l amperes 

 I "practical" emu 

 o. I cgs emu 



2. 9982 X 10^ cgs esu 



Electromotive Force: 



I international volt = 

 1.00043 absolute volts 

 1.00084 int'n'l volts (U. S. before 191 1) 

 1. 00130 int'n'l volts (England, before 



1906) 

 1. 00106 int'n'l volts (England, 1906-08) 

 I.OOOIO int'n'l volts (England, 1909-10) 

 1.00032 int'n'l volts (Germany, before 



1911) _ 

 1.00032 int'n'l volts (France, before 1911) 



I absolute volt = 

 °- 99957 int'n'l volt 

 I "practical " emu 

 10* cgs emu 

 o- 0033353 cgs esu 



Quantity of Electricity: 



(Same as current equivalents.) 

 I international coulomb = 



1/3600 ampere-hour 



1/96500 faraday 



Capacity: 



I international farad = 

 o. 99948 absolute farad 



I absolute farad = 

 1.00052 int'n'l farads 

 I "practical " emu 

 io~^ cgs emu 

 8. 9892 X 10" cgs esu 



Inductance: 



I international henry = 

 1.00052 absolute henries 



I absolute henry = 



0. 99948 int'n'l henry 

 I " practical " emu 

 10^ emu 



1. II 24 X io~i2 cgs esu 



Energy and Power: 



(standard gravity = 980.665 cm/sec/sec.) 

 I international joule = 

 1 . 00034 absolute joules 



I absolute joule = 

 o. 99966 int'n'l joule 

 10' ergs 



o. 737560 standard foot-pound 

 o. 101972 standard kilogram-meter 

 0.277778x10"^ kilowatt-hour 



Resistivity: 



I ohm-cm = 0.393700 ohm-inch 



= 10,000 ohm (meter, mm-) 

 = 12,732.4 ohm (meter, mm) 

 = 393>7oo microhm-inch 

 = 1,000,000 microhm-cm 

 = 6,015,290 ohm (mil, foot) 



I ohm (meter, gram) = 5710. o ohm (mile, 



pound) 



Magnetic Quantities: 



I int'n'l gilbert = 0.99991 absolute gilbert 

 I absolute gilbert = i. 00009 int'n'l gilberts 

 I int'n'l maxwell = i . 00043 absolute maxwells 

 I absolute maxwell = o. 99957 int'n'l maxwell 

 I gilbert = 0.7958 ampere-turn 



I gilbert per cm =0. 7958 amjjere-turn per 

 cm 

 = 2. 021 ampere-turns per 

 inch 

 I maxwell = i line 



= io~* volt-second 

 I maxwell per cm^ = 6. 452 maxwells per in* 



Smithsonian Tables, 



