The Metric System

Inquiry Question

• In what ways could you measure these trees?

Physical SciencePhysical Science

Measurement

Length Volume Mass

Chapter Goals

• To explain what matter and energy are• To tell why measurement is important• To use the basic metric units of length,

volume, and mass• To explain the meaning of prefixes used

with metric units of measurements• To calculate area and volume, using

metric units• To convert metric units.

Lesson 1 – What is Physical Science

• Lesson Objectives– Explain and define physical science– Explain matter– Name two areas of physical science– Describe some tools of physical scientists.

Lesson 1

• Have you ever wondered how your smart phone works?

• Have you ever stopped to think about how a computer or digital camera works?

• Do you ever ponder the workings of a complex machine?

• Each of these questions can be answered by studying physical science!

Lesson 1

• Physical Science is the study of matter and energy.– Matter is anything that has mass and takes

up space.– Can you name things that are made of

matter?– What do all of these things have in common?

Lesson 1

The Study of Matter and Energy

• All matter has something in common– All matter has mass.

• Mass is the amount of material that an object has

• Energy is different than matter– Energy is needed to make things move (the

ability to do work)– It cannot be seen or held

• Can you think of some forms of energy?

Lesson 1

Two Areas of Physical Science

• Chemistry– Chemistry is the study of matter and how it

changes.• Used to explain things like rain, rust and burning

• Chemistry has brought us new medicines, food, clothing, and materials.

– Can you name something that is a product of chemistry?

Lesson 1

Two Areas of Physical Science

• Physics– Physics is the study of energy and how it acts

with matter.• Used to explain things like flight, engines, and all

movement.• Our understanding of physics has brought us such

things as cellular phones, computers, televisions, space satellites, and jet airplanes.

Lesson 1

Tools of Physical Scientists

• Skills such as observing, classifying, measuring, organizing, inferring, predicting, modeling, analyzing, and communicating.– What are some tools that scientists can use to

help them with doing any of the above?

Lesson 1

Review:– What is physical science?– What are the two areas of physical science?– What kinds of things do scientists in each

area study?– What are three tools that scientists use to do

experiments?– What is matter?

Lesson 2 – Why Scientists Measure

• Lesson Objectives– Explain why measurements are important– Explain the importance of using units that are

the same for everyone

Lesson 2

• Measurements are important because:– we often cannot trust our senses– our senses are not sensitive enough

Lesson 2

• Units of Measurement– A known amount in measurement is called a

unit– Familiar units include the yard, mile, minute,

and day.• Can you name any other units?

– Early units were often based on parts of the body.

• Can you name any units we use today that are named for parts of the body?

• Can you imagine why this would not be a very good system to use today?

Lesson 2

– Early units were often based on parts of the body.

• Can you name any units we use today that are named for parts of the body?

• Can you imagine why this would not be a very good system to use today?

Lesson 2

Systems of Measurement

• In the United States, we use the customary system, which includes units such as the foot, inch, and pound.– The customary system is hard to work with

because the units of measure don’t clearly relate to each other.

• Ex: 1 foot = 12 inches, but 1 mile = 5280 feet

Lesson 2

Systems of Measurement

• Scientists and most other people throughout the world use the metric system.– The metric system has a number of

advantages over the customary system.• It is simpler to use.• It is easier to remember.• It is the systems we will use this year.

Lesson 2

Review:

• Why are measurements important?

• Why is it important to use units of measurements that are the same for everyone?

• What are some common units in the customary system of measurement?

• What is the name of the system of measurement that scientists use?

Lesson 3 – Using Metric Units to Measure Length

Lesson Objectives

• Identify and explain the common metric units of length.

• Explain the meaning of prefixes used with metric units of measurements.

Lesson 3

Money Analogy

• The metric system is based on a system on tens – similarly to how our system of currency is set up.– 10 pennies are equal to a dime– 10 dimes are equal to a dollar– 10 dollars are equal to a ten dollar bill

Lesson 3

Lesson 3

Using Meters

• The meter (m) is the standard metric unit used to measure length– A meter is a little bit longer than a yard– A football field is just over 90 meters long– The common tool used for measuring length

in the metric system is called the meter stick

Lesson 3

Using Meters

• Meter sticks are often divided into smaller, equal units– In this close up of a meter stick, you can

see the smaller divisions.

An example of a meter stick

Lesson 3

Using Meters• If a meter is divided up into 100 equal

parts, each part is called a centimeter.• Centimeters are useful if what you want to

measure is too small to easily measure with a meter– Measuring the width of a book would be

awkward with a meter, but could easily be done with a centimeter ruler.

– The abbreviation for a centimeter is (cm).

Lesson 3

Using Meters

• Sometimes even a centimeter is too large of a unit to use for measuring an object.– If a meter is divided into 1000 equal parts,

each part is called a millimeter.– A millimeter is abbreviated (mm).

Lesson 3

Using Meters

• Sometimes when we measure things that are really big using meters, we can get a very large number.

• To make things easier, we can use a unit called a kilometer that is equal to 1000m

• A kilometer is abbreviated (km)

Lesson 3

Length Equivalents

10 millimeters 1 centimeter

1000 millimeters 1 meter

100 centimeter 1 meter

1000 meter 1 kilometer

Lesson 3

Using Metric Prefixes

• The prefixes in front of the word meter have special meanings.

• They are used to show how many times the meter is multiplied or divided.– Centi means 1/100th

– Milli means 1/1000th

– Kilo means 1000

Lesson 3

Some Metric Prefixes

Prefix Meaning Units and its Abbreviation

Kilo- (k) 1000 x Kilometer (km)

Centi- (c) _1_ (0.01)

100

Centimeter (cm)

Milli- (m) _1__ (0.001)

1000

Millimeter (mm)

Lesson 3

Review• Which letter in the figure below marks 1 millimeter?• Which letter shows 1 centimeter?• How many millimeters are there in 1 centimeter?• How many millimeters are there in 10 centimeters?• What is the measurement in millimeters of the match?

What is it in Centimeters?

Lesson 4 - Using Metric Measurements to Find Area

• Lesson Objectives– Explain and define area. – Calculate area in metric units

Lesson 4

You Can use measurements of length to calculate other measurements. – One example of a calculated measurement is

area.• Area is the amount of surface an object has.

– To find the area of a rectangle, multiply the length by its width.

• Units must be the SAME!• Express the answer in square units by putting a

small 2 at the upper right of the unit.

Lesson 4

Example 1:

1 cm x 1 cm = 1 cm2

Example 2:

2 cm x 3 cm = 6 cm2

Lesson 4

Review:

Find the area for each of the rectangles in the table.

Length Width Area

8 cm 7.2 cm 57.6 cm2

8 m 8 m

3.4 mm 5.2 mm

2.6 m 4.7 m

13 m 5.1 km

Lesson 5 - Using Metric Measurements to Find Volume

• Lesson Objectives– Explain what volume is. – Calculate volume in metric units– Convert metric units of volume

Lesson 5

Another calculation that you can make using metric measurements is volume.– Volume describes the amount of space an

object takes up. – Another calculation that you can make using

metric measurements is volume.

Lesson 5

Volume of a Rectangular Prism

• The box below measures 1 cm on each edge.– You can find the volume of this box by

multiplying its length by its width by its height– The small 3 in the upper right hand corner

means cubic• 1 cm x 1 cm x 1 cm = 1 cm3

Lesson 5

• This larger box has a length of 3 cm, a width of 2 cm and a height of 2 cm.– Its volume can be calculated by multiplying

the three measurements together.3 cm x 2 cm x 2 cm = 12 cm3

Lesson 5

Volume of a Liquid

• Another metric unit for volume is the liter.

• A liter is slightly larger than a quart.

• The abbreviation for the liter is L.

• A liter is the same volume as a box that is 10 cm on each side, or 1000 cm3

Lesson 5

Table of Equivalent Volumes

Volume Equivalents

1 Liter (L) 1,000 cubic centimeters

1 cubic centimeter (cm3) 0.001 L

1 milliliter (mL) 0.001 L

1 milliliter (mL) 1 cubic centimeter (cm3)

Lesson 5Review: 1. A box measures 8 cm by 9 cm by 12 cm. What is its volume?2. What is the volume of a stainless-steel container with a length of

18 mm, width of 20 mm, and a height of 10 mm?3. Find the volume of a cabinet that measures 1.2 m by 5 m by 75

cm (Hint: convert so all of the units are the same)4. A box is 5 cm high, 4 cm wide, and 9 cm long. What is the

volume in cubic centimeters? What is the volume in milliliters?5. Convert each of these measurements.

a. 3 L = ______ ml b. 5.5 L = ______ ml

c. 3000 cm3 = ______ L d. 3700 cm3 = _______ L

e. 0.72 L = ______ mL f. 350mL = _______ cm3

Lesson 6 – Using Metric Units to Measure Mass

Lesson Objectives

• Identify the basic metric unit of mass.

• Convert metric units of mass.

Lesson 6

• Mass is the amount of material an object has.

• The gram is the metric unit for mass.– It equals the mass of 1 cm3 of water.

• This is about the same mass as a small paper clip.

Lesson 6

Mass Equivalents• The same prefixes that were used with length

and volume can also be used with gram.– This helps us express very large or very small

masses in a way that makes it easier to understand.– To measure the mass of a person, you would

probably use kilograms (kg).– To measure the mass of a single hair from your head,

you would probably use milligrams (mg).

Lesson 6

Mass Equivalents

1 kilogram (kg) 1000 grams (g)

1 centigram (cg) 0.01 grams (g)

1 milligram (mg) 0.001 grams (g)

Lesson 6

Since: – 1 cm3 of water has a mass of 1 gram– 1000 cm3 of water has a mass of 1000g– 1000 g is also know as a kilogram– 1000 cm3 is also a known as a Liter

Then: – 1 Liter of water has a mass of 1 kg

Lesson 5

Review:Convert the following measurements1. 6 g = ___ mg2. 80000 g = ___kg3. 90 g = ___cg4. 3000 cg = ___mg5. 25300 mg = ___kg6. 10 g = ___ mg7. Which is larger – 5 g or 49 cg?8. Which is smaller – 850 g or 0.9kg?