Bell Ringer
• Get out a sheet of paper…
• What is the metric system based on?
The Metric System
• The metric system is an internationally
standardized system of units of
measurement.
• The metric system is based on a base unit
and prefixes.
The metric system was
created to develop a
unified, natural, universal
system of measurement.
In 1790 King Louis XVI
of France assigned a
group to begin this task.
As of 2005, only three
countries, the United
States, Liberia, and
Myanmar, have not
changed over to the metric
system. The official
modern name of the
metric system is the
International System of
Units or abbreviated SI.
The SI system is used universally
for all scientific purposes so the
metric system will be the only
system of measurement we will be
using in science this year.
The metric system was developed based on decimals. The base
units are converted by factors of 10 by simply moving the decimal
place. A prefix is then added to the base unit to indicate a larger or
smaller unit.
The base unit for length is the meter. The meter was originally
defined as 1/10,000,000th of the distance from the North Pole to the
Equator through Paris. The meter is now defined as the distance
traveled by light in an absolute vacuum in 1/299,792,458 of a second
(don’t worry – you don’t have to remember this).
The base unit for mass in the metric system is the gram. Mass is a
measurement of how much matter is in an object. Mass is
measured using a balance. One gram is about the same as a small
paper clip.
Double pan balance
Mass of
about one
gram
Triple beam balance
Volume is the measurement of how much space an object
occupies. Liquid volume is measured with a graduated cylinder.
Solid volume can be calculated with a formula or by water
displacement. The basic unit for volume in the metric system is the
liter.
One liter sodas can be
purchased at
convenience stores.
Water displacement
Graduated cylinder
Volume formula for a rectangular prism
is length x width x height.
Temperature is the measurement of the heat of something on a scale.
The basic unit of temperature in the metric system is Celsius or
centigrade. Water freezes on the Celsius scale at 0° and boils at
100°. Temperature is measured with a thermometer.
Thermometer
Water at freezing point measured
by a digital thermometer
The metric system uses prefixes added to the base unit to represent
larger or smaller units. Each prefix is a multiple of 10.
Prefix
Abbreviation
Word value
Number
value
kilo
km
one
thousand
1000
hecto
hm
one hundred
100
deka
dam
ten
10
deci
dm
one tenth
0.1
centi
cm
one
hundredth
0.01
milli
mm
one
thousandth
0.001
Length Units in Metric System
kilometer
hectometer
dekameter
meter
decimeter
centimeter
millimeter
Most Common Volume
Units in Metric System
liter
milliliter
Most Common Mass
Units in Metric System
kilogram
gram
milligram
Metric mass can be expressed in terms of metric volume. One gram
of mass equals one milliliter in volume. One milliliter equals one
centimeter cubed.
If one milliliter equals one
gram then 1000 milliliters
or 1 liter equals 1000 grams
or 1 kilogram.
kilogram/liter
Ladder Method
1
2
KILO
1000
Units
3
HECTO
100
Units
DEKA
10
Units
DECI
0.1
Unit
Meters
Liters
Grams
How do you use the “ladder” method?
1st – Determine your starting point.
2nd – Count the “jumps” to your ending point.
3rd – Move the decimal the same number of
jumps in the same direction.
CENTI
0.01
Unit
MILLI
0.001
Unit
4 km = _________ m
Starting Point
Ending Point
How many jumps does it take?
4. __. __. __. = 4000 m
1
2
3
Conversion Practice
Try these conversions using the ladder method.
1000 mg = _______ g
1 L = _______ mL
160 cm = _______ mm
14 km = _______ m
109 g = _______ kg
250 m = _______ km
Compare using <, >, or =.
56 cm
6m
7g
698 mg
Metric Conversion Challenge
Write the correct abbreviation for each metric unit.
1) Kilogram _____
4) Milliliter _____
7) Kilometer _____
2) Meter _____
5) Millimeter _____
8) Centimeter _____
3) Gram _____
6) Liter _____
9) Milligram _____
Try these conversions, using the ladder method.
10) 2000 mg = _______ g
15) 5 L = _______ mL
20) 16 cm = _______ mm
11) 104 km = _______ m
16) 198 g = _______ kg
21) 2500 m = _______ km
12) 480 cm = _____ m
17) 75 mL = _____ L
22) 65 g = _____ mg
13) 5.6 kg = _____ g
18) 50 cm = _____ m
23) 6.3 cm = _____ mm
14) 8 mm = _____ cm
19) 5.6 m = _____ cm
24) 120 mg = _____ g
Compare using <, >, or =.
25) 63 cm
26) 536 cm
6m
53.6 dm
27) 5 g
28) 43 mg
508 mg
5g
29) 1,500 mL
30) 3.6 m
1.5 L
36 cm