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The Metric System
Workshop
This short presentation will go over the units
used in the metric system, their naming
conventions, and how to convert between
different metric units.

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What Americans Are Used To
 The English Standard System
 Inches and gallons and pounds (oh my!)
 Many different units
 Inches, feet, yards, miles, …
 Ounces, cups, pints, quarts, gallons, …
 Many conversion factors
 12 inches in a foot
 5280 feet in a mile
 16 ounces in a pound
 Fractional units
 ¼ inch, ½ gallon, ¾ pound, …

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Why People Like the Metric System
 No piles of zeros
 Just prefixes
 No arbitrary conversion factors or fractions
 Only decimals
 Easy to pronounce and write
 Short names and simple letter symbols
 World standard
 It’s used to define the English Standard
System!

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What’s the metric system all
about?

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It’s All About Three Basic Units
 Meters
 Length, e.g., your height
 Represented by the letter m
 One meter is a few inches longer than a yard
 Liters
 Volume, e.g., the size of a car’s gas tank
 Represented by the letter l or L
 One liter is a little more than a quart
 Grams
 Mass, e.g., the mass of a penny
 Represented by the letter g
 One gram is a little over one thirtieth of an ounce

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And It’s All About Prefixes
NAME
 Giga
 Mega
 Kilo
 Deci
 Centi
 Milli
 Micro
 Nano
Magnitude
 109
 106
 103
 10-1
 10-2
 10-3
 10-6
 10-9
Symbol
 G
 M
 k
 d
 c
 m
 µ
 n
(Besides meters, liters, and grams, the prefixes are also used for other
units – seconds and bytes – that are not metric system specific)

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Putting Units and Prefixes Together
 Metric measurements consist of
 A quantity, e.g., two or 101
 An optional prefix for the magnitude of the
quantity , e.g., kilo or mega
 And one of the three basic units.
 For example
 Thirty liters
 Two kilometers
 Six decigrams

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Abbreviating Measurements
 Numbers and symbols are used to abbreviate
measurements
 The number represents the quantity
 Symbols represent the magnitude and unit
 One gram is abbreviated as 1 g
 Two meters is represented by 2 m
 Twelve milligrams is abbreviated as 12 mg
 Ten kilometers is represented by 10 km

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What Units Would You Use?
 The volume of a swimming pool
 kiloliters (kl) or megaliters (Ml)
 The mass of a car
 megagrams (Mg) or gigagrams (Gg)
 The length of a pencil
 centimeters (cm)
 The height of tree
 meters (m)
 The volume of a shoebox
 liters (L)

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Down here are the
inches. Yes, I know
they’re upside
down.
The little MM and
CM stand for
millimeters and
centimeters
So, how wide is the
dime?
The End of a Ruler
18 mm or 1.8 cm

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Converting Between Prefixes
 Sometimes we want to change from one
prefix to another
 For example, changing 3100 meters to 3.1
kilometers
 Or 0.2 microseconds to 200 nanoseconds
 To do this we use the metric conversion ruler

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109
108
107
106
105
104
103
102
101
10-1
100
10-2
10-3
10-4
10-5
10-6
10-7
10-8
10-9
giga-
(G)
mega-
(M)
kilo-
(k)
deci-
(d)
centi-
(c)
milli-
(m)
micro-
(µ)
nano-
(n)
Base unit
(g, m, L, sec, or byte)
Metric Conversion Ruler

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Using the Metric Conversion Ruler
 Change 5.3 megameters to kilometers
 Look at where the prefixes fall on the line
 Count the number of spaces between them
 Look at the direction between prefixes
 Move the decimal point 3 places to the right
 5.3 Mm = 5300 km
107
106
105
104
103
102
mega- kilo-
to the right
←3 spaces→

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Another Conversion Example
 Change 1024 milligrams to grams
 Move the decimal point 3 places to the left
 1024 mg = 1.024 g
101
100
10-1
10-2
10-3
10-4
gram milli-
3 spaces to the left

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Conversion Examples
 7.11 µg = ? ng
7110 ng
 0.2934 kg = ? dg
2934 dg
 21.665 cl = ? ml
216.65 ml
 703.94 μm = ? mm
0.70394 mm
4 spaces to the right
103
102
101
10-1
kilo- deci-
100
10-2
centi-
10-3
milli-
1 space to the right
10-3
10-4
10-5
10-6
milli- micro-3 spaces to the left
3 spaces to the right
10-6
10-7
10-8
10-9
micro- nano-
10-9

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The End
 Please download some conversion
worksheets to elp hone your skills
http://sciencespot.net/Media/metriccnvsn2.pdf