If you can understand and use: pounds, inches, gallons, or
Fahrenheit, you can learn the metric system The Metric System
Slide 2
Why Metric? A basic understanding of metric units and usage is
a necessary part of being educated and literate. While traditional
units of measure are still in widespread use in the United States
and in certain other places, metric is the standard. It is
practically everywhere and it seems the direction that the whole
world is moving towards more and more. You will see it often
throughout your lives.
Slide 3
Why Metric? The metric system is simpler and easier to use and
understand than traditional measurement systems. Because metric
uses prefixes, there is effectively a single unit for all
measurements of a certain kind (such as length or volume). Using
metric units in many cases would greatly improve communication and
comprehension. Converting to the metric system, does not need to be
overly expensive, and often it is costly to not to do so. A number
of countries already prohibit the importation of products with any
non-metric indications on the labels, and more countries will
follow. If a company must carry two different product lines just to
have metric sizes in one country and non-metric in another, that is
wasteful and unnecessary.
Slide 4
Why Metric? It is inevitable, ultimately. The world has decided
on metric. At the moment, about 95% of the population of the world
lives in a country that is metric or getting close. These people
represent 70-80% of the world economy, a figure which has been
rising for 60 years.
Slide 5
Learning Metric If you can understand and use pounds, inches,
gallons, or Fahrenheit, you can learn metric. The metric system is
not hard to learnmost people just try to learn it the hard
way.
Slide 6
Rule #1: Don't try to do conversions between metric and
non-metric. Forget about the old units for now. If I weigh myself
and find that I am 65 kilograms, then I now have an idea of what 65
kg means. Theres no need to know what that is in pounds. I also
know that a 0.5 liter bottle full of water weighs half a kilogram.
Now I have some reference points to build a mental framework for
what a kilogram means. It doesn't mean a certain number of pounds;
it means a weight that can be related to our own experience.
Slide 7
Rule #2: Metric does not necessarily mean "math problems". But
if you do need to do some arithmetic involving measurements,
there's no better way. Do you have to do math problems when you buy
a gallon of milk or look at a thermometer that shows Fahrenheit? Of
course not. Then why would you need to know lots of math to buy a
two-liter bottle of Sprite or look at a Celsius thermometer? For
situations where you do need to use math, using metric units in
math is much easier than using the standard units.
Slide 8
Rule #3: Be prepared for some mental discomfort. If you are not
familiar with using a particular unit of measure, it can seem like
gibberish. ITS OK! Relating that a mental picture can involve some
effort and feelings of uncertainty. ITS OK! Keep in mind that most
people aren't experts in the non- metric units either. For example,
suppose you can see a street sign. You may not be able to say if it
is 100 meters away or 150, but how accurate would you be if you
tried to estimate it in feet?
Slide 9
Reference Points Learning metric really only requires a few
reference points and a way to use them in everyday life. To help me
use metric units, I have a Celsius thermometer, a kilogram scale, a
liter water bottle, several meter sticks, and a metric odometer and
speedometer on my bike. The first three are available at Walmart,
the meter sticks are available online from Office Depot, and you
can get a bike computer at any bike shop. When you get a
thermometer or scale, get a digital one because these will let you
to show only the metric units. It is much easier to think in the
new units if you don't have the old ones around.
Slide 10
Overview of Important Metric Units You may come across metric
units of measure with which you are unfamiliar. THAT IS OK! This
part of class is intended to introduce you to the metric units that
a literate person might be expected to know or which you may come
across in your lifetime.
Slide 11
Overview of Important Metric Units What are you measuring? What
units will you be using? Length Units used: kilometer, meter,
centimeter, millimeter, sometimes others Area Units used: any of
the above squared, also hectare (ha) Volume Units used: cubic
meter, liter, milliliter Mass Units used:("weight")metric ton,
kilogram, gram, milligram, microgram Force Units used: Newtons
Pressure Units used: bar, millibar or hectopascal, pascal
Temperature Units used: Celsius, Kelvin THIS SHOULD GO IN JOURNAL
ENTRY #1
Slide 12
Descriptions of Metric Units PrefixSymbolNumerical Meaning
Descriptive Meaning megaM1,000,000one million kilok1,000one
thousand hecto*h100one hundred deka**da10ten decid1/10one tenth
centi*c1/100one hundredth millim1/1000one thousandth
micro1/1,000,000one millionth *These prefixes have limited usage.
You will usually only see them in the centimeter, hectopascal, and
hectare. **The SI Brochure spelling of this prefix is deca-, but
the U.S. National Institute of Standards and Technology (NIST)
recommends deka-
Slide 13
Length The length units are probably what most people think of
when they think of the metric system, so most people are probably
fairly familiar with them. A meter is about the distance from the
floor to a doorknob. Sometimes, you may see a kilometer informally
referred to as a "klick".
Slide 14
English vs. Metric Units Left Image:
http://webapps.lsa.umich.edu/physics/demolab/controls/imagedemosm.aspx?picid=1167
Right Image: http://share.lancealan.com/N800%20ruler.jpg Which is
longer? A. 1 mile or 1 kilometer B. 1 yard or 1 meter C. 1 inch or
1 centimeter 1.6 kilometers 1 mile 1 yard = 0.9444 meters 1 inch =
2.54 centimeters
Slide 15
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 1299,792,458 of a
second. Metric Units 1 Kilometer (km) = 1000 meters 1 Meter = 100
Centimeters (cm) 1 Meter = 1000 Millimeters (mm) Which is larger?
A. 1 meter or 105 centimeters B. 4 kilometers or 4400 meters C. 12
centimeters or 102 millimeters D. 1200 millimeters or 1 meter
Slide 16
Measuring Length Ruler:
http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg How
many millimeters are in 1 centimeter? 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. 1 centimeter = 10 millimeters 2.8 28 3
Slide 17
Area To specify area, use square meters (m 2 ), hectares (ha),
or square kilometers (km 2 ). A hectare is the area of a square 100
m on a side, which means it is 10,000 m 2. There are 100 ha in one
km 2. A hectare covers about two and a quarter football fields.
With the metric system it is easy for farmers and others to figure
out how much water covers how much area. For example, one liter of
water covers one square meter to a depth of one millimeter. So, 10
cm of water that covers 1 m 2 is 100 L. Likewise, 1 mm of water
covering 1 ha equals 10,000 L, and 1 mm of water over 1 km 2 equals
1 million liters.
Slide 18
Volume You may already be familiar with liters and milliliters.
Just as there are 1000 milliliters in one liter, there are 1000
liters in one cubic meter. In various metric areas of the world,
prefixes besides "milli" are often used with liters. So in France
you may find a bottle labeled in centiliters, and in Australia you
may get a water bill showing your consumption in kiloliters, or see
a news report mentioning megaliters.
Slide 19
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
gallon = 3.79 liters It would take approximately 3 1-liter bottles
to equal a gallon. 1 fl oz = 29.573 ml 1 12-oz can of soda would
equal approximately 355 ml. 1 quart = 0.946 liters
Slide 20
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 cm 3 (or cc) = 1 gram* Which is larger? A. 1
liter or 1500 milliliters B. 200 milliliters or 1.2 liters C. 12 cm
3 or 1.2 milliliters* * When referring to water Liter Image:
http://www.dmturner.org/Teacher/Pictures/liter.gif
Slide 21
Measuring Volume 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 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.
Slide 22
Measuring Liquid Volume Images created at
http://www.standards.dfes.gov.uk/primaryframework/downloads/SWF/measuring_cylinder.swf
What is the volume of water in each cylinder? Pay attention to the
scales for each cylinder.
Slide 23
Measuring Solid Volume 10 cm 9 cm 8 cm We can measure the
volume of regular object using the formula length x width x height.
_____ X _____ X _____ = _____
http://resources.edb.gov.hk/~s1sci/R_S1Science/sp/e
n/syllabus/unit14/new/testingmain1.htm We can measure the volume of
irregular object using water displacement. Amount of H 2 O with
object = ______ About of H 2 O without object = ______ Difference =
Volume = ______
Slide 24
Mass (weight?) Weight really means the Mass multiplied by the
Force of Gravity. (on earth it is 9.8m/s/s) Weight = Mass X Gravity
Mass measures come in multiples of 1000: a thousand milligrams per
gram, a thousand grams per kilogram, etc. Water weighs one gram per
milliliter, one kilogram per liter, and one metric ton per cubic
meter. You have seen medicine and vitamins labeled in milligrams,
and perhaps in micrograms well.
Slide 25
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
pound = 453.6 grams 100 kilogram = 220 pounds 1 ounce of gold =
28,349.5 milligrams
Slide 26
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 Svres, France. Metric Units 1 Kilogram (km) =
1000 Grams (g) 1 Gram (g) = 1000 Milligrams (mg) Which is larger?
A. 1 kilogram or 1500 grams B. 1200 milligrams or 1 gram C. 12
milligrams or 12 kilograms D. 4 kilograms or 4500 grams Kilogram
Prototype Kilogram Prototype Image -
http://en.wikipedia.org/wiki/Kilogram
Slide 27
Weight To understand body weight in kilograms, it is best to
get a scale (or change the setting on yours if you can). These can
be some reference points: A Newborn baby 2500 - 4000 g (2.5 - 4.0
kg) A Lightweight adult 55 - 75 kg A Medium-weight adult 70 - 100
kg A Really big football player 140 kg If you get a scale, you can
weigh yourself with and without a backpack full of books or other
items to find out how much the backpack weighs.
Slide 28
Force The metric unit for force is the Newton (N). This is one
area that may seem less familiar to newcomers to the metric system.
Normally, you won't have to worry about Newtons, but they do come
up in a few situations. For example, the lift on the back of a
truck may have its capacity measured in Newtons. A Newton is about
the weight of 100 grams. So, an apple weighs about 1 N. A good rule
of thumb is that an object's weight in Newtons is ten times its
mass (weight) in kilograms. So, if a person is about 59 kg, they
weigh approximately 590 N.
Slide 29
Pressure The measurement of pressure can seem bewildering at
first glance, because there are so many units that have
historically been used. However, there are now just two metric
units that are generally used, and they are closely related: the
Pascal and the bar. The modern unit for pressure is the Pascal
(Pa). The Pascal is a very small unit, so people often use another
unit called the bar, which is defined to be 100,000 Pa. The bar is
demonstrating the pressure of the atmosphere, hence its name (the
barometric pressure). In weather reports, pressure is usually given
in millibar (mb or mbar) or hectopascal (hPa). They both the same:
100 Pa. Sometimes, pressure is given in kilopascals (kPa). Air
pressure is normally in the range of 980 mb to 1030 mb.
Slide 30
Temperature In everyday life, we measure temperature in degrees
Celsius when we use metric, of course. For scientific measurements,
or for very hot or cold things, we may use Kelvins (such as for the
temperature of the sun or of liquid helium). Kelvin is like
Celsius, but shifted so that zero is at absolute zero instead of
the freezing point of water. Water freezes at 273.15 Kelvins.
Incidentally, we do not speak of degrees Kelvinit's just Kelvins.
To understand the basics of Celsius temperatures just remember:
Thirty's warm, Twenty's nice, Ten's cold, Zero's ice. That is
really all you need to know most of the time, except perhaps the
boiling point of water (100 C) and body temperature (37 C).
Slide 31
Height To understand a person's height in centimeters, it is
best to tape a meter stick to the wall so you and others can
measure the height directly. These can be some reference points:
New-born baby (length) 50 cm Average man (18 yrs. old) 177 cm (90%
are between 167 and 185 cm) Average woman (18 yrs. old) 164 cm (90%
are between 156 and 171 cm) Tall basketball player 200 cm (2
meters)
Slide 32
Millimeters One very simple thing you can do to begin using
millimeters is to change your word processor, and other software on
your computer, to use millimeters instead of inches. After a few
weeks of using 20 mm margins or 25 mm margins, it feels completely
natural to use mm instead of using inches.
Slide 33
Small volumes and weights I recently got a kitchen food scale
that shows weights up to 2 kg. Now I can know that I ate 100 g of
pasta (before cooking) last night! One thing you can do right now
to help you understand grams is to look at the package for a loaf
of bread. The serving size will probably be one slice, with a
weight in grams given. If you get out a slice and see how heavy it
feels, you have a reference point right there in your kitchen. When
you go to the grocery store, instead of looking at the ounces or
fluid ounces on the label, pay attention to the milliliters (mL),
liters (L), grams (g), and kilograms (kg). If you have a water
bottle that is either 500 mL or 1 L, you can just look at the size
of the bottle an get an idea of how much those quantities are. The
two liter soda bottle can also serve as a reference point. If you
have a box of cereal that weighs 425 g, you just see how heavy the
box feels to get an idea of how much 425 g is.
Slide 34
Elevation (distance above sea level) Compare the elevation of
your town (Shelley, Idaho(1,412 m) to these values: U-2 Spy plane:
about 27,000 m Passenger jets: about 10,000 m Mt. Everest: 8,850 m
Denali/McKinley: 6,194 m Salt Lake City: 1,300 m Chicago: 204 m
Florida's highest point: 105 m Death Valley: 86 m Dead Sea: 411
m
Slide 35
Astronomical Measurements Most of these measurements are just
FYII wouldn't expect the average citizen to know many of these. An
exception would be the Earth-Sun distance or the Earth's
circumference. Earth-Sun distance: 150,000,000 km Earth-Moon
distance: 385,000 km Earth circumference: 40,000 km Geostationary
orbit: 35,786 km above surface of Earth Earth radius: 6,370 km Moon
radius: 1,737 km Low Earth orbit: about 250 km above surface of
Earth U-2 Spy plane: 27 km above surface of Earth
Slide 36
The Conversion of the United States There seems to be the
general impression in the United States that the metric system was
something that they tried years ago and it didn't stick. It will
always be an issue until we change. Metrication is inevitable as
the world becomes more global and as the metric system becomes more
and more entrenched in engineering, business, and everyday life in
countries everywhere.
Slide 37
What Has Been Happening? There was a push to convert the United
States back in the 1970's. Similar programs were quite successful
in many countries (such as Australia), but in the United States the
effort was largely derailed by a lack of commitment. Since that
time, metrication has been occurring at a slow pace. Many of our
industries and corporations have been converting and often use
metric. These include the automotive industry, electronics
companies, and companies such as Kodak. Most recently, consumer
products have started appearing in metric sizes (such as some
shampoo, mouthwash, bottled drinks, etc.). Over the past few
decades, while we have been making slow progress in conversion,
other countries around the world have been developing their
economies and solidifying their use of the metric system.
Slide 38
Where Are We Now? The attitude of many in America has been that
others should just deal with our measurement system. However, 95%
of the world now lives in countries that are entirely or mostly
metric. Worldwide use of the metric system has solidified even
during America's reign as superpower. We simply are not able to
impose our system on the rest of the world. Many other countries
are recognizing this and they are taking steps to enforce metric
usage in trade because metric units are the accepted international
standards. Many of our trading partners require or soon will
require all imports of commodities to be labeled in metric units
only.
Slide 39
Where Are We Now? For example, it is against the law for a
company to import a soft- drink bottle into Korea if it is labeled
"20 FL OZ (591 mL)". It would be filled to 600 mL and be labeled in
milliliters, no ounces allowed. Similar laws will apply in the
European Union within a few years. Thus, a global soft-drink
manufacturer needs two different product lines (with different
product sizes) to maintain the U.S. measures in the United States.
Some trade groups have complained that these laws are protectionist
measures, but they simply require that the accepted standards be
followed. U.S. companies are not penalized if they just comply. For
this reason, many large U.S. companies have already converted their
products to metric sizes, and many more will do so in the near
future.
Slide 40
What Happens Next? In order to help our companies produce goods
for a world market, some are suggesting that we change U.S. law to
allow metric-only labels on consumer goods. This means that
customers will be seeing more and more metric when they go to the
grocery store. In 2005, proposed legislation to allow metric-only
labeling was going to be submitted to Congress, but it was not,
primarily because of opposition from the Food Marketing Institute.
It is not clear what will happen next, but the European Union was
given assurance in 1999 that the legislation would be passed by
2010 so that we can stop inflicting our units of measure on them in
international trade. Keep an eye out for more metrics popping up in
your life!
Slide 41
The Metric T kilohectodekaUnitsdecicentimilli khdagramsdcm
liters meters Can you figure out the meaning of these?: kg mm daL
mg cm kg
Slide 42
KILO 1000 Units HECTO 100 Units DEKA 10 Units DECI 0.1 Unit
CENTI 0.01 Unit MILLI 0.001 Unit Meters Liters Grams Ladder Method
How do you use the ladder method? 1 st Determine your starting
point. 2 nd Count the jumps to your ending point. 3 rd Move the
decimal the same number of jumps in the same direction. 4 km =
_________ m 1 2 3 How many jumps does it take? Starting Point
Ending Point 4. 1 __. 2 3 = 4000 m This should go in Journal Entry
#1
Slide 43
Try these conversions using the ladder method. 1000 mg =
_______ g 1 L = _______ mL160 cm = _______ mm 14 km = _______ m109
g = _______ kg 250 m = _______ km Conversion Practice Compare
using, or =. 56 cm 6 m 7 g 698 mg
Slide 44
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 Metric Conversion Challenge kg m g mL mm L km cm mg 2
104,000 4.8 5000.198.075.5 560 160 2.5 65,000 63.12 5600.8
Slide 45
Compare using, or =. 25) 63 cm 6 m 27) 5 g 508 mg 29) 1,500 mL
1.5 L 26) 536 cm 53.6 dm 28) 43 mg 5 g 30) 3.6 m 36 cm < = <
< =