THE METRIC SYSTEM OF MEASUREMENT

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THE METRIC SYSTEM
OF MEASUREMENT
Middle School Science
Table of Contents
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History of Measurement
Customary vs. Metric Systems
History of Metric System
Reading Scales
Significant Figures
Metric Measurement – Length
Metric Measurement – Mass
Metric Measurement – Volume
Density
History of Measurement

Body Parts – Ancient Units of
Measurement
Thumb
(inch)
 Foot
(foot)
 Pace
(yard)
 Distance from nose to tip of
outstretched thumb
(yard)
 Handspan – thumb to 1st finger
 Palm – width of palm
 Cubit – elbow to tip of fingers
 Fathom – between outstretched
hands
 Digit – width of index finger

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Why do we need set units of measurement?

Consistency
 Body
parts, steps, etc. are
many different sizes
 Body parts change in size
over a lifetime
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History of the Metric System
1670
Gabriel Mouton (France)
 1790
Thomas Jefferson proposed a decimalbased measurement system for the U.S.
 1790
France proposed
 1840
France requires metric use
 1866
U.S. makes use of Metric system LEGAL,
but not mandatory (Metric Act of 1866)
 1900
35 countries accept the Metric system
 Today
Metrics used in U.S. in areas:

 Federal Government Program
 FDA required use of dual units on all consumer products
 National Weather Service (Celcius)
 U.S. Stock Exchange
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King Henry's Story
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Customary vs. Metric – Ease of Use
Customary Units
2
3
10
12
2
8
1760
16
2000
5280
1 ft
____ in
1 cm
____
mm
1 yd
____ ft
1 dm
____ cm
1 mile
____ ft
1m
____ dm
1 mile
____ yd 1 dkm
____ m
1 lb
____ oz
____dk
m
1 ton
____lbs 1 km
____ hm
1 cup
____ fl.
oz
1 cL
____ mL
1 pt
____ c
1 cg
____ mL
1 qt
____ pt
1m
____dk
m
4
10
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Metric Units
1 hm
Metric Conversions
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Reading Scales
Reading
Scales Wks.
Reading
Scales Module
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Significant Figures
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Metric System – Length
The
distance between two points
Meter
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(m)
Metric
Mania
Metric System – Length
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Metric System – Length Lab
Object
Blue
Block
(length)
Paper
(length)
Paper
(width)
Popcycle
Stick
Streak
Plate
Table
Height
Lego
(length)
Lego
(width)
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Pencil
(length)
Toothpic
km
m
cm
mm
Metric Measurement - Volume
Volume – the amount of space something
takes up
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Liquid volume – Liters
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 kL,
hL, dkL, L, dL, cL, mL
Solid Volume – Cubic centimeters (cm3)

1 mL = 1 cm3
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Metric
Mania
Metric Measurement - Volume

Finding the volume of a cube or
rectangular prism
V=LxWxH
 V = 4cm x 6 cm x 3 cm
 V = 24 cm2 x 3 cm
 V = 72 cm3
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L = 4 cm
W = 6 cm
H = 3 cm
Metric Measurement - Volume

Finding the volume of a cylinder
V = πr2 x h
r = 4 cm
 V = 3.14 (4cm)2 x 3cm
 V = 3.14 (16 cm2) x 3 cm H = 3 cm
 V = 50.24 cm2 x 3 cm
 V = 150.72 cm3
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Metric System - Volume
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Metric Measurement - Mass
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Metric
Mania
Density
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Why does a ship
float?
What happens when
you throw an empty
can or a stick into
the water?
Why?
Coke Demonstration
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Density – the
average mass per
unit of volume
How much matter is
“squeezed” into a
given space
Density
Info.
Calculating Density
Mass of a substance divided by its volume
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D = M/V
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Unit – gram/cm3
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Density
Info.
Calculating Density
Mass of 1 mL of water = _____________
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Volume of 1 mL of water = _______________
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D= m / v
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Density
Info.
Densities of Common Substances
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Item / Substance
Density (g/cm3)
Mercury
13.6
Lead
11.3
Wood (avg.)
0.8
Steel
7.8
Gold
19.3
Aluminum
2.8
Plastic
1.17
Air
0.0.118
Table sugar
1.587
Table salt
2.164
Glass
2.2
Corn oil
0.925
Platinum
21.4
Density
Info.
Answers

Why does a ship (made of steel, wood, glass,
etc.) float on the water?

Why does the Diet Coke can float, while the
Coke can sinks? What is different about
them? What can we infer?
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Density
Info.
DENSITY
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Density
Measure of MASS per unit VOLUME.
How packed parts of a material are.
Density = MASS divided by VOLUME
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D=M/V
Density = Mass/Volume
1. Find the Mass using the triple beam
balance.
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Density = Mass/Volume
1.
Find the Mass using the triple beam balance.
2.
Find the Volume of the object
using L x W x H.
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Density = Mass/Volume
1.
2.
Find the Mass using the triple beam balance.
Find the Volume of the object
using L x W x H.
3.
Divide Mass by Volume
Mass
Volume
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Density = Mass/Volume
1. Find the Mass using the triple beam balance.
2. Find the Volume using Water
Displacement.
3. Mass divided by Volume
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Density Calculations
Volume = __________
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Mass = ____________
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Density =
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Density Calculations
Length = ____________
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Width = ____________
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Height = ____________
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Mass = ____________
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Density =
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Density Lab
•Measure the
L,W,H, &
Mass of
object.
•Then
calculate
volume and
density of
object.
Lesson 1:
Length
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T. Trimpe 2008 http://sciencespot.net/
English vs. Metric Units
Which is longer?
A. 1 mile or 1 kilometer
B. 1 yard or 1 meter
C. 1 inch or 1 centimeter
1 mile
1.6 kilometers
1 inch = 2.54 centimeters
1 yard = 0.9444 meters
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Left Image: http://webapps.lsa.umich.edu/physics/demolab/controls/imagedemosm.aspx?picid=1167
Right Image: http://share.lancealan.com/N800%20ruler.jpg
Metric Units
The basic unit of length in the metric system in the meter and is represented by a
lowercase m.
Standard: The distance traveled by light in absolute vacuum in 1⁄299,792,458 of a
second.
Metric Units
1 Kilometer (km) = 1000 meters
1 Meter = 100 Centimeters (cm)
Click the image to
watch a short video
about the meter.
1 Meter = 1000 Millimeters (mm)
Which is larger?
A. 1 meter or 105 centimeters
C. 12 centimeters or 102 millimeters
B. 4 kilometers or 4400 meters
D. 1200 millimeters or 1 meter
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Measuring Length
How many millimeters are in 1 centimeter?
1 centimeter = 10 millimeters
What is the length of the line in centimeters? _______cm
What is the length of the line in millimeters? _______mm
What is the length of the line to the nearest centimeter? ________cm
HINT: Round to the nearest centimeter – no decimals.
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Ruler: http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg
Lesson 2:
Mass
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T. Trimpe 2008 http://sciencespot.net/
English vs. Metric Units
Which is larger?
1. 1 Pound or 100 Grams
2. 1 Kilogram or 1 Pound
3. 1 Ounce or 1000 Milligrams
1 ounce of gold =
28,349.5 milligrams
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1 pound = 453.6 grams
100 kilogram =
220 pounds
Metric Units
Mass refers to the amount of matter in an object.
The base unit of mass in the metric system in the kilogram and
is represented by kg.
Standard: 1 kilogram is equal to the mass of the International
Prototype Kilogram (IPK), a platinum-iridium cylinder kept
by the BIPM at Sèvres, France.
Metric Units
1 Kilogram (km) = 1000 Grams (g)
1 Gram (g) = 1000 Milligrams (mg)
Kilogram Prototype
Click the image to
watch a short video
about mass.
Which is larger?
A. 1 kilogram or 1500 grams
C. 12 milligrams or 12 kilograms
B. 1200 milligrams or 1 gram
D. 4 kilograms or 4500 grams
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Kilogram Prototype Image - http://en.wikipedia.org/wiki/Kilogram
Measuring Mass
We will be using triple-beam balances to
find the mass of various objects.
The objects are placed on the scale and
then you move the weights on the beams
until you get the lines on the right-side of
the scale to match up.
Once you have balanced the scale, you add up the
amounts on each beam to find the total mass.
What would be the mass of the object measured
in the picture?
_______ + ______ + _______ = ________ g
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Top Image: http://www.southwestscales.com/Ohaus_Triple_Beam_750-SO.jpg
Bottom Image: http://www.regentsprep.org/Regents/biology/units/laboratory/graphics/triplebeambalance.jpg
Measuring Mass – Triple-Beam Balance
1st – Place the film canister on the scale.
2nd – Slide the large weight to the right until the arm drops below the line.
Move the rider back one groove. Make sure it “locks” into place.
3rd – Repeat this process with the top weight. When
the arm moves below the line, back it up one groove.
4th – Slide the small
weight on the front
beam until the lines
match up.
5th – Add the amounts on each beam to find the total mass to the nearest tenth of a
gram.
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Click here to try an online activity.
Lesson 3:
Volume
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T. Trimpe 2008 http://sciencespot.net/
English vs. Metric Units
Which is larger?
A. 1 liter or 1 gallon
B. 1 liter or 1 quart
C. 1 milliliter or 1 fluid ounce
1 fl oz = 29.573 ml
1 12-oz can of soda
would equal
approximately 355 ml.
1 quart = 0.946 liters
1 gallon = 3.79 liters
It would take approximately 3 ¾ 1liter bottles to equal a gallon.
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Metric Units
Volume is the amount of space an object takes
up.
The base unit of volume in the metric system in
the liter and is represented by L or l.
Standard: 1 liter is equal to one cubic decimeter
Metric Units
1 liter (L) = 1000 milliliters (mL)
1 milliliter (mL) = 1 cm3 (or cc) = 1 gram*
Which is larger?
A. 1 liter or 1500 milliliters
Click the image to
watch a short video
about volume.
B. 200 milliliters or 1.2 liters
C. 12 cm3 or 1.2 milliliters*
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* When referring to water
Liter Image: http://www.dmturner.org/Teacher/Pictures/liter.gif
Measuring Volume
We will be using graduated cylinders to find
the volume of liquids and other objects.
Read the measurement based on the bottom of the
meniscus or curve. When using a real cylinder, make
sure you are eye-level with the level of the water.
What is the volume of water in the cylinder? _____mL
What causes the meniscus?
A concave meniscus occurs when the molecules of the liquid
attract those of the container. The glass attracts the water on the
sides.
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Top Image: http://www.tea.state.tx.us/student.assessment/resources/online/2006/grade8/science/images/20graphicaa.gif
Bottom Image: http://morrisonlabs.com/meniscus.htm
What is the volume of water in each cylinder?
A
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B
Pay attention to the scales for each cylinder.
C
Images created at http://www.standards.dfes.gov.uk/primaryframework/downloads/SWF/measuring_cylinder.swf
Measuring Liquid Volume
Measuring Solid Volume
9 cm
We can measure the volume of regular object
using the formula length x width x height.
8 cm
_____ X _____ X _____ = _____
We can measure the volume of
irregular object using water displacement.
Amount of H2O with object = ______
About of H2O without object = ______
Difference = Volume = ______
Click here for an online activity about volume.
Choose Lessons à Volume & Displacement
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http://resources.edb.gov.hk/~s1sci/R_S1Science/sp/en
/syllabus/unit14/new/testingmain1.htm
10 cm
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