MEASUREMENT Mr. Peterson SCIENCE Center Grove Middle School North

Measurement  Describe the world using numbers  Types of Measurement include:  Distance, time, speed, volume, mass…  Measurement can also help describe events

Metric System  Called the International System of Units or SI  Decimal system based on 10’s  Prefixes include:  Milli (1/1000 th )  Deci (1/10 th )  Kilo (1000)

Metric System  Used by scientists all over the world to measure length, volume, mass, weight, density, and temperature.  King Hector Doesn’t Usually Drink Chocolate Milk KILOHECTODEKAUNITDECICENTIMILLI

Precision and Accuracy  Precision is the closeness of repeated measurements to each other.  Accuracy is the closeness of a measured or derived data value to its true value. precise = repeatable accurate = true Practice

Precision and Accuracy  Significant digits are necessary when calculating  DON’T COUNT Zeros at the end of the number without a decimal (ex. 1300) OR Zeros at the beginning of a decimal (ex ).  When adding or subtracting, use the smallest number you use.  Example: Answer in significant digits = 7.7 significant digits = 4 significant digits = 2

Precision and Accuracy  Scientific notation is used so large numbers are easier to understand.  Move the decimal point until only 1 nonzero number remains on the left. Count the number of places you moved the decimal and use that number as a power of ten  Examples: = x = 4.5 x = x 10 4

Length  Distance from one point to another  METER (M) is the basic unit  1M = 100cm  1M = 1000mm  1km = 1000M

Volume  Amount of space an object takes up  Liter (L) is the basic unit of LIQUID volume  Cubic centimeter (cm 3 ) is the basic unit of SOLID volume

Mass  Amount of matter in an object  Gram (g) is the basic unit

Weight  Amount of attraction between two objects due to gravity  Newton (N) is the basic unit  MASS AND WEIGHT ARE NOT THE SAME!

Density  Mass per unit volume of a substance  g/mL is the basic unit  Formula: Density = Mass divided by Volume Density = g/mL  Density of water is 1gram/milliliter  If an object’s density is less then one it will float.  If an object’s density is greater then one it will sink.

Temperature  Measure of hotness and coldness  Celsius (C°) is the basic unit  Water freezes at 0° degree Celsius and boils at 100° degrees Celsius.