**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 × 10^{10}

Thus: 1 emu of charge = 2.998 × 10^{10} esu of charge or 1 abcoulomb = 2.998 × 10^{10} statcoulomb