Sally Student

Horace Mann Middle School

WHY USE METRICS? Based on powers of

10 so it is easy to convert

Used by almost all of the countries in the world

It is the language of scientists How far is it?

(In America we would say 59 miles)

10

01

10

10

HOW DID IT GET STARTED? The modern metric system is

really called the Systeme International d’Unités (SI)

The original system was first proposed in 1585 by Simon Stevin in his book “The Tenth” – he suggested that a decimal system be used for weights and measures, coinage, and divisions of the degree of arc

HOW DID IT GET STARTED?(Part 2)

Thomas Jefferson (1790) proposed a decimal-based measurement system for the United States

France’s Louis XVI (1790) authorized scientific investigations aimed at a reform of French weights and measures – these investigations led to the first “metric” system

HOW DID IT GET STARTED?(Part 3)

The U.S. Mint (1792) produced the world’s first decimal currency (the U.S. dollar has 100 cents)

France (1795) officially adopted the metric system

1954 – The International System of Units began its development

BASIC UNITS

There are three basic units used in the metric system (SI):

1. gram (mass)2. meter (distance)3. liter (volume)

They are all related.

RELATIONSHIPS BETWEEN BASICS

1 meter (m) is 1/10,000,000 of the distance between the Equator and the North Pole

1/100 of a meter is a centimeter (cm) 1 cubic centimeter (cm3) of water

equals 1 gram (g) The volume occupied by 1 cm3 is 1

milliliter (mL)

Forward to Common Symbols

THEREFORE:

1 cm3 = 1 mL 1 cm3 of water = 1 g (= 1 mL) 1 L of water = 1 kg (= 1 dam)

(SEE HOW EASY THIS IS?)

COMMON SYMBOLS

Back to Relationships

g gram k kilo 1000

m meter h hecto 100

L liter da deka 10

d deci 0.1

c centi 0.01

m milli 0.001

METRIC CONVERSIONSKilo-

Hecto-

Deka-

BASE = METER, LITER, GRAM

Deci-

Centi-

Milli-

1000

100

10

1

0.1

0.01

0.0010

MOVE DECIMAL ONE PLACE TO RIGHT FOR EACH STEP

MOVE DECIMAL ONE PLACE TO LEFT FOR EACH STEP

For an example, click here

For an example, click here

SAMPLE CONVERSIONS I Example 1: How many meters are in

1 kilometer?

There are 3 steps in the down-to-the-right direction between kilo- and the base (meter), so move the decimal point three places to the right, therefore there are 1000 meters in 1 kilometer!

Back to Metrics Conversions

SAMPLE CONVERSIONS II

Example 2: How many dekaliters are there in 2345 milliliters?

There are 4 steps in the up-to-the-left direction between milli- and deka-, move the decimal point four places to the left, therefore there are 0.2345 dekaliters in 2345 milliliters!

Back to Metric Conversions

PRACTICE CONVERTING1. 11 cm = _____ mm2. 0.55 m = _____ cm3. 1.23 kg = _____ mg4. 0.47 L = _____ hL5. 1001 g = _____ kg6. 357 mL = _____ daL7. 131 dm = _____ km8. 2001 kL = _____ mL

Answer these before going to the next slide

PRACTICE CONVERTING (ANSWERS)

1. 11 cm = 110 mm2. 0.55 m = 55 cm3. 1.23 kg = 1,230,000 mg4. 0.47 L = 0.0047 hL5. 1001 g = 1.001 kg6. 357 mL = 0.0357 daL7. 131 dm = 0.0131 km8. 2001 kL = 2,001,000,000 mL How did you do?

OTHER SI STANDARDSMEASUREMENTMASS (LARGER)TIMETEMPERATUREDENSITYVELOCITYFORCEPRESSUREENERGYPOWERELECTRICAL CURRENT

STANDARDMETRIC TONSECONDDEGREE CELSIUSKG PER CUBIC METERKM PER HOURNEWTONKILOPASCALKILOJOULEWATTAMPERE

REFERENCES FOR THE “METRIC SYSTEM”

Clip art images courtesy of Microsoft Office 2002

The U.S. Metric Association, http://lamar.colostate.edu/~hillger/

Padilla, Michael J., Ph.D., Physical Science. Needham, Massachusetts: Prentice-Hall, 2001.