Irodov – Problems in General Physics

28. Units of Physical Quantities

Names and symbols of certain quantities

A, ampere H, henry Oe, oersted

a.m.u., atomic h, hour Q, ohm

mass unit Hz, hertz P, poise

B, bel 7, joule Pa. pascal

b, barn K, kelvin rad, radian

C, coulomb 1, litre S, siemens

cd, candela lm, lumen s, second

D, diopter lx, lux sr, steradian

dyn, dyne m, metre St, stokes

eV, electron-volt min, minute T, tesla

F, farad mol, mole V, volt

G, gauss Mx, maxwell W, watt

g, gram N, newton Wb, weber

Decimal Prefixes

Factor Name of prefix Symbol Factor Name of prefix Symbol

1012 tera- T^10 -2^ centi- c

109 giga- G 10 -3 milli- m

106 mega- M 10-6 micro- 11

103 kilo- k 10 -9 nano- n

102 hecto- h 10 -12 pico- p

10 deca- da 10 -15 femto- f

10 -1 deci- d 10 -18 atto- a

SI and CGS Units

Physical quantity

Name of unit Conversion factor

SI CGS 1 SI unit/1 CGS unit

Length m cm 100
Time s s 1
Velocity m/s cm/s 100
Acceleration m/s 2 cm/s 2 100
Oscillation frequency Hz Hz 1
Angular velocity rad/s rad/s 1
Angular frequency s - 1 s-1 1
Mass kg g 103
Density kg/m 3 g/cm 3 10 -3
Force N dyn 105

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