pico (p), nano (n), micro(µ), milli (m), centi (c), kilo (k), mega (M), giga (G), tera (T); Mass (kg); Length (m); Volume (L); Time (s); Electric Current (A); Temperature (K); Intensity of light (Cd); amount of a substance (mol)
You should:
(a) be able to explain that some physical quantities consist of a numerical magnitude and a unit;
(b) be able to use the correct unit for its physical quantity;
(c) know how the prefixes and their symbols indicate decimal sub-multiples or multiples of units;
(d) be able to make suitable estimates of physical quantities.
In 1960, the Eleventh General Conference on Weights and Measures was held in Paris. They adopted a universal system of measurement units called Le Systeme International d'Unites (French), which is a revised version of the metric system. This International System, or SI, as it is commonly referred to, is used for commerce and Science around the world.
There are seven SI base units. Everything that is measurable, can be measured by these base units, or by units derived from these bases. The table below shows the bases, their international symbols, and what they are used to measure.
Quantity |
Unit |
Abbreviation |
Mass |
kilograms |
kg |
Length |
meters |
m |
Time |
seconds |
s |
Electric Current |
ampere |
A |
Temperature |
Kelvin, Celsius |
K,C |
Intensity of light |
candela |
cd |
amount of a substance |
mole |
mol |
The following table shows the numerical prefixes that with the ones you must know shaded in.
Factor |
Name |
Symbol |
10^{24} |
yotta |
Y |
10^{21} |
zetta |
Z |
10^{18} |
exa |
E |
10^{15} |
peta |
P |
10^{12} |
tera |
T |
10^{9} |
giga |
G |
10^{6} |
mega |
M |
10^{3} |
kilo |
k |
10^{2} |
hecto |
h |
10^{1} |
deka |
da |
10^{-1} |
deci |
d |
10^{-2} |
centi |
c |
10^{-3} |
milli |
m |
10^{-6} |
micro |
µ |
10^{-9} |
nano |
n |
10^{-12} |
pico |
p |
10^{-15} |
femto |
f |
10^{-18} |
atto |
a |
10^{-21} |
zepto |
z |
10^{-24} |
yocto |
y |
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