The Metric System from Industry Week, 1981 November 30

Metric System Basics

The Metric System Used in nearly every country in the world, the Metric System was devised by French scientists in the late 18th century. The goal of this effort was to produce a system that used the decimal system rather than fractions as well as a single unified system that could be used throughout the entire world. S.I. = System Internationale

Metric System The metric system is based on a base unit that corresponds to a certain kind of measurement Length = meter Volume = liter Mass = gram Prefixes plus base units make up the metric system Example: Centi + meter = Centimeter Kilo + liter = Kiloliter

Quantity Definitions: Length = the distance between two points; the longest dimension of an object Volume = the amount of space taken up by something Mass = the amount of matter an object has triple beam balance meter stick metric ruler graduated cylinder

Metric System So if you needed to measure length you would choose meter as your base unit Length of a tree branch 1.5 meters Length of a room 5 meters Length of a ball of twine stretched out 25 meters

Quantity measured Unit Symbol Relationship Length, width, distance, thickness, girth, etc. millimeter mm 10 mm = 1 cm centimeter cm 100 cm 1 m meter m   kilometer km 1 km 1000 m Mass (“weight”)* milligram mg 1000 mg 1 g gram g kilogram kg 1 kg 1000 g metric ton t 1 t 1000 kg Time second s Temperature degree Celsius °C Area square meter m² hectare ha 1 ha 10 000 m² square kilometer km² 1 km² 100 ha Volume milliliter mL 1000 mL 1 L cubic centimeter cm³ 1 cm³ 1 mL liter L 1000 L 1 m³ cubic meter m³

Quantity measured Unit Symbol Relationship Speed, velocity meter per second m/s   kilometer per hour km/h 1 km/h = 0.278 m/s Density kilogram per cubic meter kg/m³ Force newton N Pressure, stress kilopascal kPa Power watt W kilowatt kW 1 kW 1000 W Energy kilojoule kJ megajoule MJ 1 MJ 1000 kJ kilowatt hour kW·h 1 kW·h 3.6 MJ Electric current ampere A

Metric Staircase kilo- hecto- deca- Key units deci- cent- milli- 1000 meter, m liter, L gram, g 100 deca- Key units 10 1 deci- cent- 0.1 0.01 milli- 0.001

Converting with the Metric System King Henry Drinks Milk During Castle Meetings Kilo- Hecto- Deca- Meter Deci- Centi- Milli- 1000 100 10 1 0.1 .01 .001 1000 m = ______ km .001 hg = ______ dg 42.7 L = _____ cL

Metric System Summary Base units in the metric system are meter, liter, gram Metric system is based on powers of 10 For conversions within the metric system, each “step” is 1 decimal place to the right or left Using the diagram below, converting to the right, moves the decimal to the right and vice versa kilo hecto deca meter liter gram deci centi milli

Metric System The three prefixes that we will use the most are: kilo centi milli kilo hecto deca Base Units meter gram liter deci centi milli

Prefixes T tera 1012 1 000 000 000 000 trillion G giga 109 billion    M mega 106 1 000 000 million    k kilo 103 1 000 thousand    h hecto*   102 100   hundred    da deka* 101 10 ten 1 one    d deci* 101 0.1 tenth    c centi* 102 0.01 hundredth    m milli 103 0.001 thousandth    µ micro 106 0.000 001 millionth    n nano 109 0.000 000 001 billionth    p pico 1012 0.000 000 000 001 trillionth

Metric System Centimeters are 10 times larger than millimeters so it takes more millimeters for the same length 1 centimeter = 10 millimeters Example not to scale 40 41 1 mm 40 41 1 cm

Metric System But what if you need to measure a longer distance, like from your house to school? Let’s say you live approximately 10 miles from school 10 miles = 16093 meters 16093 is a big number, but what if you could add a prefix onto the base unit to make it easier to manage: 16093 meters = 16.093 kilometers (or 16.1 if rounded to 1 decimal place)

Metric System These prefixes are based on powers of 10. What does this mean? From each prefix every “step” is either: 10 times larger or 10 times smaller For example Centimeters are 10 times larger than millimeters 1 centimeter = 10 millimeters

Metric Staircase kilo- hecto- deca- Key units deci- cent- milli- 1000 0.1 0.01 milli- 0.001

Converting with the Metric System When converting within the metric system it is simply a measure of moving the decimal in the appropriate direction.

Metric System For each “step” to right, you are multiplying by 10 For example, let’s go from a base unit to centi 1 liter = 10 deciliters = 100 centiliters 2 grams = 20 decigrams = 200 centigrams ( 1 x 10 = 10) = (10 x 10 = 100) (2 x 10 = 20) = (20 x 10 = 200) kilo hecto deca meter liter gram deci centi milli

Metric System An easy way to move within the metric system is by moving the decimal point one place for each “step” desired Example: change meters to centimeters 1 meter = 10 decimeters = 100 centimeters or 1.00 meter = 10.0 decimeters = 100. centimeters kilo hecto deca meter liter gram deci centi milli

Metric System Now let’s try our previous example from meters to kilometers: 16093 meters = 1609.3 decameters = 160.93 hectometers = 16.093 kilometers So for every “step” from the base unit to kilo, we moved the decimal 1 place to the left (the same direction as in the diagram below) kilo hecto deca meter liter gram deci centi milli

Metric System If you move to the left in the diagram, move the decimal to the left If you move to the right in the diagram, move the decimal to the right kilo hecto deca meter liter gram deci centi milli

Metric System Now let’s start from centimeters and convert to kilometers 400000 centimeters = 4 kilometers 400000 centimeters = 4.00000 kilometers kilo hecto deca meter liter gram deci centi milli

Metric System Now let’s start from meters and convert to kilometers 4000 meters = 4 kilometers kilo hecto deca meter liter gram deci centi milli Now let’s start from centimeters and convert to meters 4000 centimeters = 40 meters kilo hecto deca meter liter gram deci centi milli

Metric System Now let’s start from meters and convert to centimeters 5 meters = 500 centimeters kilo hecto deca meter liter gram deci centi milli Now let’s start from kilometers and convert to meters .3 kilometers = 300 meters kilo hecto deca meter liter gram deci centi milli

Metric System Now let’s start from kilometers and convert to millimeters 4 kilometers = 4000000 millimeters or 4 kilometers = 40 hectometers = 400 decameters = 4000 meters = 40000 decimeters = 400000 centimeters = 4000000 millimeters kilo hecto deca meter liter gram deci centi milli