Metric System - Lowry Science · The metric system uses prefixes to indicate units larger or...
Transcript of Metric System - Lowry Science · The metric system uses prefixes to indicate units larger or...
METRIC SYSTEM
HISTORY OF MEASUREMENT
as their fundamental unit of length. Legend has it that this Greek unit was based on an
People measured a yard of cloth by the distance between the end of the outstretched arms and their chin.
The Romans measured their pace steps, of about 2.5 feet, 1000 double paces formed a mile.
HISTORY OF MEASUREMENT
caused confusion in measurement!So, the French decided to create a standard unit of measurement
you can say International System of Units. Better yet you can say
system of unit for measurement. Most countries use the SI unit of measurement. To date the United States has not made the move towards changing from the Standard English Measurement System to the SI system.
Countries by date of
metrication
COMPARING ENGLISH TO METRIC SYSTEM
Measurements grew out of the creative way that people measured for themselves. Familiar objects and parts of the body were used as measuring devices. For example, people measured shorter distances on the ground
was a thousand paces). They measured capacities with common household items such as cups, pails, and baskets. The word gallon comes from an old name for a pail. Unfortunately, these creative measuring devices allowed for different measurements to be obtained when different people measured the same items. Eventually, a standard was set so that all measurements represented the same amount for everyone.
In the metric system, each of the common kinds of measure length, weight, capacity has one basic unit of measure. To measure smaller amounts, divide the basic unit into parts of ten, a hundred, or a thousand, and so on. To measure larger amounts, multiply the basic unit by ten, a hundred, or a thousand, and so on.
English System
Metric System
COMPARING ENGLISH TO METRIC SYSTEM
Measurement English System
Metric System
Length Inch MileFootYard
Meter
Weight/Massdifference)
OuncePoundTon
Gram
Volume Cup Quart Pint GallonOunceTeaspoonTablespoon
Liter
COMPARING ENGLISH TO METRIC SYSTEM
Measurement English System
Metric System
Length Inch MileFootYard
Meter
Weight/Massdifference)
OuncePoundTon
Gram
Volume Cup Quart Pint GallonOunceTeaspoonTablespoon
Liter
PREFIXESIn order to properly convert from one metric unit to another, you must know the prefixes AND what value they represent. A metric prefix is a modifier on the root word and it tells us the unit
millionths of grams. The metric system uses prefixes to indicate units larger or smaller than a given base unit. Each prefix is a multiple of 10.
EX: DECIMETER
Prefix Root Word
PREFIXESPREFIX SYMBOL VALUE EXPONENTIAL
kilo k 1,000 10
hecto h 100 10
deca da 10 10
BASE no symbol 1 10
deci d 0.1 10
centi c 0.01 10
milli m 0.001 10
HOW DOES THE METRIC SYSTEM WORK?No longer must you remember the relationships such as: 12 inches to a foot or 3 feet to a yard. Instead, think of the metric system in terms
of TEN. Changing one unit to another for a given measurement means moving the decimal point.
You can make the conversions by multiplying or dividing by 10 for each step.
Divide your foot steps to climb up the ladder!
Falling down the ladder will multiply your bruises!
ANOTHER WAY TO LOOK AT THEMETRIC SYSTEM:
When making metric conversions, arrange the prefixes from largest to smallest.
kilo hecto deca UNIT deci centi milli
king henry died BY
drinking chocolate milk
CONVERTING ENGLISH TO METRIC
Most jobs require that you work in either English units of Metric units, but not both. It is necessary, however, on occasion to convert units from one system to another. You just need to know that it is
few examples:
YOU WILL NOT BE RESPONSIBLE FOR KNOWING THESE CONVERSIONS!
Measure Metric to English English to MetricLength: 1mm = 0.04in
1cm = 0.39in1km = 0.62mi
1in = 2.54cm1yd = 0.914m1mi = 1.609 km
Weight: 1g = 0.035oz1l = 1.057 qt
1oz = 28.350g1lb = 0.453kg
Volume: 1mL = .2 tsp1L = 1.057qt
1tsp = 5mL1c = 236mL1gal = 3.785L
Using your new knowledge, answer the following questions:
1.______________ as their fundamental unit of ______________.
2. How did people measure a yard of cloth? ____________________________________________________________________________________________________________
3. The Romans figured that 1000 double paced steps would measure what distance? _________________
4. Why did the use of body parts not work as a form of measurement?__________________________________________________________________________________________________
5. Who created the International System of Units? ________________
6. The abbreviation for the International System of Units is ________
7. Long ago people measured capacities with common household items such as ____________, _____________, and ______________.
Using your new knowledge, answer the following questions:
8. The English System:~ Length is measured in ____________, ___________, __________,
_________, ___________~ Weight is measured in ____________, ___________,
___________~ Volume is measured in ____________, ___________, __________,
_________, ___________, _____________, ___________9. We know the International System of Units (SI) to be the
___________________________________________________
10. The Metric System Basic Units:~ Length is measured in ____________~ Mass is measured in _____________~ Volume is measured in _____________
11. Write the correct symbol for each prefix below:kilo ___ hecto ___ deca (deka) ___deci___ centi ___ milli ___
12. When combining a base unit with a prefix the unit of measurement _____________.