Related Resources: Engineering Conversions Equivalent

Electric and Magnetic Units

Engineering Conversions and Equivalents

Electric and Magnetic Units

The esu and emu unit systems are cgs systems. esu denotes “electrostatic unit”, sometimes given prefix “stat”, e.g. statcoulomb emu denotes “electromagnetic unit”, sometimes given prefix “ab”, e.g. abcoulomb Some emu units have special names:

mksq DIMENSIONS

Length =L
Mass =M
Time =T
Current =Q/T
Charge = Q

Equivalent Units mksq System

1 newton = 1 kilogram-meter/(second)2
1 volt = 1 newton-meter/coulomb
1 amp = 1 coulomb/second
1 joule = 1 newton-meter = 1 coulomb-volt
1 weber = 1 volt-second
1 farad = 1 coulomb/volt
1 henry = 1 weber/amp
1 ohm = 1 volt/amp
1 watt = 1 joule/sec

DIMENSIONS OF esu AND emu ELECTRIC AND MAGNETIC QUANTITIES
The fundamental dimensions in both systems are M, L, T. cgs units used.

*c = velocity of light (free space) in cm/sec ≈ 3 × 10¹⁰
Thus: 1 emu of charge = 2.998 × 10¹⁰ esu of charge or 1 abcoulomb = 2.998 × 10¹⁰ statcoulomb