SI Units and Metric Prefixes

The Magnitudes of Physics uses the International System (SI) of weights and measures to specify parameter values. Dr. Russ Rowlett, Director of the Center for Mathematics and Science Education at the University of North Carolina at Chapel Hill, has compiled an excellent summary of the SI system.

Given the great range of the exponents in The Magnitudes of Physics, one can understand the value of metric prefixes to avoid, when possible, the use of large exponents. The following table from Dr. Rowlett's web site summarizes the common and uncommon metric prefixes that have been approved by the General Conference on Weights and Measures.

yotta- (Y-)

10²⁴

1 septillion

zetta- (Z-)

10²¹

1 sextillion

exa- (E-)

10¹⁸

1 quintillion

peta- (P-)

10¹⁵

1 quadrillion

tera- (T-)

10¹²

1 trillion

giga- (G-)

10⁹

1 billion

mega- (M-)

10⁶

1 million

kilo- (k-)

10³

1 thousand

hecto- (h-)

10²

1 hundred

deka- (dk-)

10

1 ten

deci- (d-)

10^-1

1 tenth

centi- (c-)

10^-2

1 hundredth

milli- (m-)

10^-3

1 thousandth

micro- (µ-)

10^-6

1 millionth

nano- (n-)

10^-9

1 billionth

pico- (p-)

10^-12

1 trillionth

femto- (f-)

10^-15

1 quadrillionth

atto- (a-)

10^-18

1 quintillionth

zepto- (z-)

10^-21

1 sextillionth

yocto- (y-)

10^-24

1 septillionth

This page was originally designed by John Lahr.

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