The Metric System

Measurement

Scientists use a single, standard system of

measurement called ___________ or

__________________________________________

SISIInternational System of UnitsInternational System of Units

Based on powers of

Main Base Units

Mass -

Volume -

Length -

Time -

Gram (g)Gram (g)

Liter (L)Liter (L)

Meter (m)Meter (m)

Second (s)Second (s)

Prefixes change the value of the base units.

Base unit

Kilo-

1000

Hecto –

100Deca-

10

Deci-

1/10 or 0.1 Centi –

1/100 or 0.01

Milli-

1/1000 or 0.001

Larger Unit PrefixesLarger Unit Prefixes

Smaller Unit PrefixesSmaller Unit Prefixes

To convert to a larger unit, move decimal point to left or divide

To convert to a smaller unit, move decimal point to right or multiply

Try these practice conversions…

1000 mg = ______ g ?

1st – What is the base unit? 2nd – Going from smaller mg to larger g3rd – move decimal 3 places to the left

Answer is: 1 g1 g

1 L = _____ mL ?

1st – What is the base unit? Liters2nd – Going from larger L to smaller ml3rd – move decimal 3 places to the right

Answer is: 1000 mL1000 mL

160 cm = _____ mm ?

1st – Going from larger cm to smaller mm

2rd – move decimal 1 place to the right

Answer is: 1600 mm1600 mm

14 km = _____ m

1st – Going from larger km to smaller m

2rd – move decimal 3 places to the right

Answer is: 14,000 m14,000 m

75 mL = _____ L

1st – Going from smaller mL to larger L

2rd – move decimal 3 places to the left

Answer: 0.075 L0.075 L

Simple Metric Conversions to Remember:

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

• 1 Kilometer (km) = 1 Kilometer (km) = 1000 meters (m)• 1 Kilogram (kg) = 1 Kilogram (kg) = 1000 grams (g)

• 1000 Kilograms (kg) = 1000 Kilograms (kg) = 1 metric ton (t)

• 1 Gram (g) = 1 Gram (g) = 1000 milligrams (mg)• 1 Liter (L) = 1 Liter (L) = 1000 milliliters (mL)• 1 Liter (L) = 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

Temperature

• Celsius CCelsius C°°

To convert from Fahrenheit to Celsius use this equation:

C° = (F° - 32) x 5/9 C° = (F° - 32) x 5/9

FormulasVolume – how much space an object occupies

VV == l l xx w w xx h h

* Units written as cubed – for ex. cm3

FormulasDensity – how tightly packed matter is within an object

DD == Mass/VolumeMass/Volume

* Obtain mass in grams or mg on balance

Units written as grams/cm3 or

grams/mL

Finding the Mean• Take the average

1. Add up all the data points

2. Divide by total number of data points

Ex: 92, 95, 94, 89, 10092, 95, 94, 89, 1001st - 92 + 95 + 94 + 89 + 100 = 470

2nd - 470 ÷ 5 = ?

Answer is : 94

GraphingTechniques

1. X- Axis

Contains the independent variable

Y - axis

Contains the dependent variable

3. Numbering intervals on each axis must be consistent

Acceptable:Acceptable:5, 10, 15, 20, 25, 30 ….etc.1, 2, 3, 4, 5, 6, 7 ….100, 200, 300, 400, 500 …

NOTNOT: 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