DIMENSIONS AND UNITS To get the value of a quantity in Gaussian units, multiply the value ex- pressed in SI units by the conversion factor. Multiples of 3 in the conversion factors result from approximating the speed of light c = 2.9979 1010 cm/sec × 3 1010 cm/sec. ≈ × Dimensions Physical Sym- SI Conversion Gaussian Quantity bol SI Gaussian Units Factor Units

t2q2 Capacitance C l farad 9 1011 cm ml2 × m1/2l3/2 Charge q q coulomb 3 109 statcoulomb t × q m1/2 Charge ρ coulomb 3 103 statcoulomb 3 3/2 density l l t /m3 × /cm3 tq2 l Conductance siemens 9 1011 cm/sec ml2 t × 2 tq 1 9 1 Conductivity σ siemens 9 10 sec− 3 ml t /m × q m1/2l3/2 Current I,i ampere 3 109 statampere t t2 × q m1/2 Current J, j ampere 3 105 statampere 2 1/2 2 density l t l t /m2 × /cm2 m m 3 3 3 Density ρ kg/m 10− g/cm l3 l3 q m1/2 Displacement D coulomb 12π 105 statcoulomb l2 l1/2t /m2 × /cm2 1/2 ml m 1 4 Electric field E volt/m 10− statvolt/cm t2q l1/2t 3 × 2 1/2 1/2 ml m l 1 2 Electro- , volt 10− statvolt 2 motance EmfE t q t 3 × ml2 ml2 Energy U, W joule 107 erg t2 t2 m m Energy w,ǫ joule/m3 10 erg/cm3 2 2 density lt lt

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ml ml Force F newton 105 dyne t2 t2 1 1 Frequency f,ν hertz 1 hertz t t 2 ml t 1 11 Impedance Z ohm 10− sec/cm tq2 l 9 × 2 2 ml t 1 11 2 Inductance L henry 10− sec /cm q2 l 9 × Length l l l meter (m) 102 centimeter (cm) 1/2 q m 3 Magnetic H ampere– 4π 10− oersted 1/2 intensity lt l t turn/m × ml2 m1/2l3/2 Magnetic flux Φ weber 108 maxwell tq t m m1/2 Magnetic B tesla 104 gauss tq l1/2t induction l2q m1/2l5/2 Magnetic m,µ ampere–m2 103 oersted– t t moment cm3 1/2 q m 3 Magnetization M ampere– 4π 10− oersted lt l1/2t turn/m × q m1/2l1/2 4π Magneto- , ampere– gilbert 2 motance MmfM t t turn 10 Mass m, M m m kilogram 103 gram (g) (kg) ml ml Momentum p, P kg–m/s 105 g–cm/sec t t m m 2 1 2 Momentum kg/m –s 10− g/cm –sec l2t l2t density ml 1 Permeability µ 1 henry/m 107 — q2 4π ×

12 Dimensions Physical Sym- SI Conversion Gaussian Quantity bol SI Gaussian Units Factor Units

t2q2 Permittivity ǫ 1 farad/m 36π 109 — ml3 × q m1/2 Polarization P coulomb/m2 3 105 statcoulomb l2 l1/2t × /cm2 2 1/2 1/2 ml m l 1 2 Potential V,φ volt 10− statvolt t2q t 3 × ml2 ml2 Power P watt 107 erg/sec t3 t3 m m Power watt/m3 10 erg/cm3–sec lt3 lt3 density m m Pressure p, P pascal 10 dyne/cm2 lt2 lt2 2 q 1 9 1 Reluctance ampere–turn 4π 10− cm− 2 R ml l /weber × 2 ml t 1 11 Resistance R ohm 10− sec/cm tq2 l 9 × 3 ml 1 9 Resistivity η,ρ t ohm–m 10− sec tq2 9 × ml ml Thermal con- κ, k watt/m– 105 erg/cm–sec– 3 3 ductivity t t deg (K) deg (K) Time t t t second (s) 1 second (sec) ml m1/2l1/2 Vector A weber/m 106 gauss–cm potential tq t l l Velocity v m/s 102 cm/sec t t m m Viscosity η,µ kg/m–s 10 poise lt lt

1 1 1 1 Vorticity ζ s− 1 sec− t t ml2 ml2 Work W joule 107 erg t2 t2

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