Do Now Complete the handout you picked up from the front door. Put HW to be checked on desk. Put tonight’s HW in HW folder. Write tonight’s HW in your agenda. Get out your ruler and binder to take notes.

Metric System Unit 1 Day 3 Greeter: Read today’s objectives

DID YOU KNOW It’s a metric world The united states is the only western country not presently using the metric system as its primary system of measurement. The only other countries in the world not using metric system as their primary system of measurement are Yemen, Brunei, and a few small islands; see Fig

DID YOU KNOW In 1906, there was a major effort to convert to the metric system in the United States, but it was opposed by big business and the attempt failed. The Trade Act of 1988 and other legislation declare the metric system the preferred system of weights and measures of the U.S. trade and commerce, call for the federal government to adopt metric specifications, and mandate the Commerce Department to oversee the program. The conversion is currently under way; however, the metric system has not become the system of choice for most Americans’ daily use.

DID YOU KNOW Lost in space In September 1999, the United States lost the Mars Climate Orbiter as it approached Mars. The loss of the $125 million spacecraft was due to scientists confusing English units and metric units. Two spacecraft teams, one at NASA’s Jet Propulsion Lab (JPL) in Pasadena, CA, and the other at a Lockheed Martin facility in Colorado, where the spacecraft was built, were unknowingly exchanging some vital information in different units. The missing Mars Climate Orbiter

American vs. Metric Length American standard 1 mile = 1760 yards = (5280 feet) 1 yard = 3 feet 1 foot = 12 inches 1 mil = 1 / 1,000 inch Metric standard 1 kilometer = 1000 meters 1 meter = 10 decimeters 1 decimeter = 10 centimeters (  1 meter = 100 centimeters) 1 centimeter = 10 millimeters Conversion: 1 inch is defined to be exactly 2.54 cm in July, 1959.

Metric System The metric system is based on a base unit that corresponds to a certain kind of measurement Length = meter Volume = liter Weight (Mass) = gram Temperature = celsius

Metric System The units of the metric system are made up of prefixes and base units. – Example: centi + meter = centimeter – Example: kilo + gram = kilogram 8 PrefixBase Unit

How to remember different lengths in the metric system: When you think of a millimeter (mm) think of: – The thickness of a dime. When you think of a centimeter (cm) think of: – The width of your pinky.

How to remember different lengths in the metric system: When you think of a meter (m) think of: – The height of the doorknob. When you think of a kilometer (km) think of: – A little more than half of a mile

Metric System The three prefixes that we will use the most are: – kilo – centi – milli

How can you remember these??? King Henry Died by Drinking Chocolate Milk – King: Kilo – Henry: Hecto – Died: Deca – By: Base (m, L, g) – Drinking: Deci – Chocolate: Centi – Milk: Milli

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 1 cm

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

Metric System Now let ’ s try our previous example from meters to kilometers: meters = decameters = hectometers = 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)

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 hectodeca meter liter gram deci centimilli

Practice Problems 4 km = ______ m 7 m = ______ cm 20 cm = _______ mm 80 mm = ______ cm 910 cm = ______ m m = _______ km

Practice Problems km = 4000 m 7.00 m = 700 cm 20.0 cm = 200 mm 80 mm = 8.0 cm 910 cm = 9.10 m m = km

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