| Physical Quantities | SI Units and Symbols | Dimensions | cgs Units |
|---|---|---|---|
| Length | meter (m) | [L] | centimeter (cm) [1 m = 100 cm] |
| Mass | kilogram (kg) | [M] | gram (g) [1 kg = 1000 g] |
| Velocity | meter per second (m/s) | [L][T]-1 | centimeter per second (cm/s) [1 m/s = 100 cm/s] |
| Acceleration | meter per second squared (m/s2) | [L][T]-2 | gal (Gal) (=cm/s2) [1 m/s2 = 100 Gal] |
| Temperature | kelvin (K) | [K] or [L]2[M][T]-2 |
|
| Force | newton (N) | m·kg·s-2 [L][M][T]-2 |
dyne (dyn) [1 N = 105 dyn] |
| Pressure | pascal (Pa) | N/m2 [L]-1[M][T]-2 |
barye (Ba) [1 Pa = 10 Ba] |
| Energy | joules (J) | N·m [L]2[M][T]-2 |
erg (erg) [1 J = 107 erg] |
| Power | watts (W) | J/s [L]2[M][T]-3 |
erg per second (erg/s) [1 W = 107 erg/s] |
| Frequency | helz (Hz) | s-1 [T]-1 | |
| Electric Charge | coulomb (C) | A·s [A][s] | statcoulomb (statC) or franklin (Fr) [1 C = 2.998×109 statC] |
| Electric Current | ampere (A) | [A] | statAmpere (statA) or franklin per second (Fr/s) [1 A = 2.998×109 statA] |
| Electric Potential | volt (V) | W/A or J/C [M][L]2[T]-3[A]-1 |
statvolt (statV) [1 V = 3.33564×10-3 statV] |
| Capacitance | farad (F) | C/V [T]4[A]2[L]-2[M]-1 |
statfarad (statF) [1 F = 8.98755×1011 statF] |
| Electric Resistance | ohm (Ω) | V/A [T]-3[A]-2[L]2[M] |
statohm (statΩ) [1 Ω = 1.11265×10-12 statΩ] |
| Electric Conductance | siemen (S) or mho (Ω-1) | A/V [T]3[A]2[L]-2[M]-1 |
|
| Magnetic Flux | weber (Wb) | V·s [T]-2[A]-1[L]2[M] |
gauss square centimeter (Gs·cm2) [1 Wb = 108 Gs·cm2] |
| Magnetic Flux Density | tesla (T) | Wb/m2 [T]-2[A]-1[M] |
gauss (Gs) [1 T = 105 Gs] |
| Magnetic Field Strength | amp per meter (A/m) | N/Wb [A][L]-1 |
oersted (Oe) [1 A/m = 1.25664×10-2 Oe] |
| Inductance | henry (H) | Wb/A [T]-2[A]-2[L]2[M] |
stathenry (statH) [1 H = 1.11265×10-12 statH] |
| Luminous Intensity | candela (cd) | [cd] | |
| Luminance | nit (nt) | cd/m2 [cd][L]-2 |
stilb (sb) [1 nt = 10-4 sb] |
| Luminous Flux | lumen (lm) | cd·steradian | |
| Illuminance | lux (lx) | lumen/m2 | |
| Radioactivity | becquerel (Bq) | second-1 [T]-1 |
|
| Absorbed Dose | gray (Gy) | J·kg-1 | |
| Dose Equivalent on the Human Body | sievert (Sv) | J·kg-1 | |
| Physical Constants | Symbols | Figures | SI Units | cgs Units |
|---|---|---|---|---|
| Speed of light (vacuum) | c | 2.997925 | 108m/s | 1010cm/s |
| Gravitational constant | G | 6.67384 | 10-11Nm2kg-2 | 10-8dyn cm2g-2 |
| Elementary charge | e | 1.60210 | 10-19C | 10-20emu |
| 4.80298 | 10-10esu | |||
| Avogadro number | N | 6.02252 | 1026kmol-1 | 1023mol-1 |
| Rest mass of an electron | me | 9.10908 | 10-31kg | 10-28g |
| 5.48597 | 10-4u (atomic mass unit) | 10-4u (atomic mass unit) | ||
| Rest mass of a proton | mp | 1.67252 | 10-27kg | 10-24g |
| 1.00727663 | u (atomic mass unit) | u (atomic mass unit) | ||
| Faraday constant | F | 9.64853365 | 104C/mol | 103emu |
| 2.89261 | 1014esu | |||
| Planck constant | h | 6.62559 | 10-34J s | 10-27erg s |
| ℏ=h/(2π) | 1.054494 | 10-34J s | 10-27erg s | |
| Reciprocal of fine-structure constant | α-1 | 137.035999 | ||
| Mass-to-charge ratio of an electron | e/me | 1.758796 | 1011C/kg | 107emu |
| 5.27274 | 1017esu | |||
| Magnetc flux quantum | Φ0=h(2e) | 2.067833758 | 10-15Wb | 10-7G cm2 |
| Bohr radius | a0 | 5.29167 | 10-11m | 10-9cm |
| Rydberg constant | R∞ | 1.0973731568539 | 107m-1 | 105cm-1 |
| Compton wavelength of electron | λc=h/(mec) | 2.4263102389 | 10-12m | 10-10cm |
| Compton wavelength of proton | λc,p | 1.321398 | 10-15m | 10-13cm |
| Bohr magneton | μB | 9.27400915 | 10-24J/T | 10-21erg/G |
| g-factor of electron | g=2|μe|/μB | 2.00231923 | ||
| Nuclear magneton | μN | 5.05050 | 10-27J/T | 10-24erg/G |
| Magnetic moment of proton | μp | 1.41049 | 10-26J/T | 10-23erg/G |
| μp/μN | 2.79274 | |||
| Magnetic moment of neutron | μn/μN | -1.91314 | ||
| Gas constant | R0 | 8.31434 | J deg-1 mol-1 | 107erg deg-1 |
| Boltzmann constant | kB | 1.3806488 | 10-23J deg-1 | 10-16erg deg-1 |