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Metric System Basics. Measurement. A measurement is a repeatable observation of a quantity that includes a number and a unit. Examples: 43 meters 16 seconds 5 liters 20 minutes 20.5 centimeters. SI SYSTEM OF MEASUREMENT.
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Measurement • A measurement is a repeatable observation of a quantity that includes a number and a unit. • Examples: • 43 meters • 16 seconds • 5 liters • 20 minutes • 20.5 centimeters
SI SYSTEM OF MEASUREMENT • Scientists worldwide have agreed to use the SI system of measurement in their work. • SI stands for “Systeme’ International” • Each type of measurement in SI has a base unit, such as the meter for distance or the second for time. • A common name for this system is the metric system.
Steps of the metric system • Divide your top two planner page boxes into 24 sections by dividing it in half vertically, then each of those sections in half and then in half again. • Divide it horizontally in thirds like the following:
Fill out your table with information • List the saying that is going to help us remember the prefixes used in the metric system. • Then fill in the name of the prefixes along with their abbreviations. • This is what the skinnier box should look like.
SI BASE UNITS • The base units we are going to work with this year are: • Meter – that is used for measuring distance • Gram – that is used for measuring mass • Liter – that is used for measuring liquid volume.
Fill out your table with base unit information and sayings • Change the saying for each of the saying for the other two base units. • List the base units that are used for each of the measurements.
Prefix names + base words • Fill in the names of each unit by adding the prefixes to the base words. • List the abbreviations for each • This is what the larger box should look like.
Multiply each of the following numbers by 10 27 x 10 = 157 x 10 = 56.4 x 10 = 458.87 x 10 = 23.516 x 10 = 270 1570 564 4588.7 235.16
Multiply each of the following numbers by 100 22 x 100 = 156 x 100 = 45.1 x 100 = 74.32 x 100 = 3.567 x 100 = 2200 15600 4510 7432 356.7
Divide each of the following numbers by 10 330 10 = 7600 10 = 268.1 10 = 1.78 10 = 18.395 10 = 33.0 or 33 760.0 or 760 26.81 0.178 1.8395
Divide each of the following numbers by 100 210 100 = 7800 100 = 521.6 100 = 82.1 100 = 7.666 100 = 2.10 or 2.1 78.00 or 78 4.216 0.821 0.07666
Guess What! If you were able to do all that without a calculator, you can do metrics.
Metric System • The metric system is based on a base unit that corresponds to a certain kind of measurement • Length = meter (m) • Volume = liter (L or l) • Weight (Mass) = gram (g) • Prefixes added to the base units make up the metric system • Example: • Centi + meter = Centimeter = cm • Kilo + liter = Kiloliter = kL or kl
Common Prefixes • The three prefixes that we will use the most in class are: • kilo • centi • milli
Example for Length • 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
Powers of 10 • 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
40 41 1 mm 1 mm 1 mm 1 mm 1 mm 1 mm 1 mm 1 mm 1 mm 1 mm 40 41 1 cm For Example • A centimeters is 10 times longer than a millimeter so it takes more millimeters for the same length 1 centimeter = 10 millimeters Example not to scale
The “Steps” • 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)
More “Steps” • 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
Applying “Steps” • 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)
Moving to the “Steps” • 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
Moving the “Steps” • Now let’s start from centiliters and convert to kiloliters 400000 centiliters = 4.00000 kiloliters 400000 centiliters = 4 kiloliters
Moving the “Steps” • Now let’s start from meters and convert to kilometers 4000 meters = 4 kilometers • Now let’s start from centigrams and convert to grams 4000 centigrams = 40 grams
Keep on Moving the “Steps” • Now let’s start from liters and convert to centiliters 5 liters = 500 centiliters • Now let’s start from kilograms and convert to grams .3 kilograms = 300 grams
Keep on Moving • 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
Finally • 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