The Metric System

International System of Units Measurement Scientists use a single, standard system of measurement called ___________ or __________________________________________ SI International System of Units

Based on powers of

Mass - Volume - Length - Time - Main Base Units Mass - Volume - Length - Time - Gram (g) Liter (L) Meter (m) Second (s)

Prefixes change the value of the base units.

Base unit Deci- Centi – Milli- Larger Unit Prefixes Kilo- 1000 To convert to a smaller unit, move decimal point to right or multiply Hecto – 100 Deca- 10 Base unit Deci- 1/10 or 0.1 To convert to a larger unit, move decimal point to left or divide Centi – 1/100 or 0.01 Milli- 1/1000 or 0.001 Smaller Unit Prefixes

Try these practice conversions…

1000 mg = ______ g ? 1st – What is the base unit? 2nd – Going from smaller mg to larger g 3rd – move decimal 3 places to the left Answer is: 1 g

1 L = _____ mL ? 1st – What is the base unit? Liters 2nd – Going from larger L to smaller ml 3rd – move decimal 3 places to the right Answer is: 1000 mL

160 cm = _____ mm ? 1st – Going from larger cm to smaller mm 2rd – move decimal 1 place to the right Answer is: 1600 mm

14 km = _____ m 1st – Going from larger km to smaller m 2rd – move decimal 3 places to the right Answer is: 14,000 m

75 mL = _____ L 1st – Going from smaller mL to larger L 2rd – move decimal 3 places to the left Answer: 0.075 L

Simple Metric Conversions to Remember:

1 meter = 100 cm 1 meter = 1000 mm 1 cm = 10 mm

1 Kilometer (km) = 1000 meters (m) 1 Kilogram (kg) = 1000 grams (g) 1000 Kilograms (kg) = 1 metric ton (t) 1 Gram (g) = 1000 milligrams (mg) 1 Liter (L) = 1000 milliliters (mL) 1 Liter (L) = 1000 cubic centimeters (cm3)

Time 60 seconds in a minute 60 minutes in an hour 24 hours in a day 52 weeks in a year 365 ¼ days in a year

C° = (F° - 32) x 5/9 Temperature Celsius C° To convert from Fahrenheit to Celsius use this equation: C° = (F° - 32) x 5/9

* Units written as cubed – for ex. cm3 Formulas Volume – how much space an object occupies V = l x w x h * Units written as cubed – for ex. cm3

* Obtain mass in grams or mg on balance Formulas Density – how tightly packed matter is within an object D = Mass/Volume * Obtain mass in grams or mg on balance Units written as grams/cm3 or grams/mL

Finding the Mean Take the average Ex: 92, 95, 94, 89, 100 1. Add up all the data points 2. Divide by total number of data points Ex: 92, 95, 94, 89, 100 1st - 92 + 95 + 94 + 89 + 100 = 470 2nd - 470 ÷ 5 = ? Answer is : 94

Graphing Techniques

1. X- Axis Contains the independent variable

Y - axis Contains the dependent variable

3. Numbering intervals on each axis must be consistent Acceptable: 5, 10, 15, 20, 25, 30 ….etc. 1, 2, 3, 4, 5, 6, 7 …. 100, 200, 300, 400, 500 … NOT: 3, 5, 6, 10, 21, 33

4. Each axis must be labeled Tell what is being shown on each axis Give the units of measurement where appropriate

5. Give your graph a TITLE!

If you are graphing more than one set of data points on a graph, set up a color key to distinguish between the different lines