THE HISTORY OF MEASUREMENTWhere did the metric system come from and what are its base units?

EARLY MEASUREMENT

The earliest types of measurement were based on body parts, objects found in nature, or human activities.

FOR EXAMPLE , ANCIENT PEOPLE USED THEIR HANDS OR HOW FAR THEY COULD WALK IN ONE DAY TO

MEASURE DISTANCE.

OR THEY USED ROCKS TO FIGURE OUT HOW MUCH SOMETHING WEIGHED.

OR THEY MEASURED AREA BY HOW MUCH LAND A PERSON

COULD PLOW IN ONE DAY.

BUT THIS CREATED PROBLEMS!

There was no STANDARD for measuring. Without a STANDARD people couldn’t agree on exactly what they were measuring. For example, if you said you wanted to trade 5 ROCKS of grain for 50 HANDS of cloth, how much you gave and got in return depended on whose HAND you used and how big the ROCKS were!

CIVILIZATIONS CREATED STANDARDS

The early Babylonians designed a system based on the GUR – the biggest box of water the king’s ass could carry.

EGYPTIANSThe EGYPTIANS used the royal

CUBIT, which was the length from pharaoh's elbow to his middle finger tip. One CUBIT was equal to 7 PALMS or 28 FINGERS.

GREEKS AND ROMANSThe Greeks and Romans use the

size of a “normal” soldier’s FOOT. That soldier’s PACE was equal to 5 FEET and a mile was 1000 PACES.

THE ENGLISH SYSTEMIn the early 1100’s an

English King tried to standardize measurement again. He used HIS foot and divided it into 12 inches (each about the width of his thumb.) One YARD became the distance from the tip of his nose to the tip of his fingers.

IT’S ALL STILL VERY CONFUSING, BUT IT’S

STANDARDIZED! 1 inch is the width of the King’s thumb 1 foot is the length of the King’s foot 1 yard is the distance from his nose to

his fingers 1 rod is equal to 20 feet 1 furlong is the length of a standard

furrow and equals 40 rods 1 mile equals 8 furlongs, of 5280 feet

HOW’S ABOUT TEMPERATURE

MEASUREMENT?In 1724 Daniel

Fahrenheit came up with our system for measuring temperature. He made 0˚ the temperature at which water froze when it was saturated with ammonium chloride.

SO WHY DOES PURE WATER FREEZE AT 32˚ AND BOIL AT 212˚?He wanted his thermometer to be easy to

make, so he set it that pure water froze at 32˚ - which was 2 x2x2x2 degrees above his 0˚

He then said that the body’s temperature was 2x2x2x2x2 degrees higher than freezing – or 96˚,

When he used those size degrees, water ended up boiling at 212˚

Simple, right?! $#%@$^&

THE FRENCH REVOLUTION!

In 1789 the French revolted and overthrew their monarchy. When they got rid of their king, they also wanted to get rid of everything that was connected to the king (like his HEAD!)

They wanted a new system of measurement that was SCIENTIFIC, UNIVERSAL, and EASY to use.

The first step was to base all measurement on the number 10. Makes for simple multiplication and conversion to different size units.

LENGTH

Started with a new unit for length. The METER! Defined 1 meter as equal to 1/10,000,000th distance from North Pole to equator going through Paris.

GOING SMALLER

To make smaller units, they divided the METER into 100 equal pieces. Each piece became a CENTIMETERS. For even smaller measurements, they divided each centimeter into tenths and got MILLIMETERS.

WHAT ABOUT VOLUME?

They started out by making a small cube that is one centimeter on a side – ONE CUBIC CENTIMETER!

1 cm

1 cm 1

cm

TOO SMALL!!One cubic centimeter is pretty darn small. It’s about the size of a sugar cube. That’s too small to use as a basic unit of volume.

THE LITERThey solve that problem

by making a BIGGER box for their standard unit for volume. The new box was 10 centimeters on a side and was called a LITER. Each LITER has 1000 CUBIC CENTIMETERS in it.

HOW DID THEY HANDLE MASS?

The basic unit for mass in the metric system is the GRAM. The French came up with the GRAM by making it equal to the mass of one cubic centimeter of water.

QUESTION!!

If one cubic centimeter of water has a mass of one gram, what is the mass of a liter of water?

LAST BUT NOT LEAST

Let’s

Talk

Temperature!

CELSIUS TEMPERATURES

Pure water freezes at 0˚ C and boils at 100˚C.

SOOOO . . That’s how we got the basic units for the metric system!

Now let’s talk about the prefixes and metric conversions.