Variables Dependent independent control Scientific Method Observation Hypothesis

Variables { Dependent, independent, control

Scientific Method Observation Hypothesis Experiment Data Collection Conclusion Retest

Experiment=A procedure to test the hypothesis. Variable – factor in the experiment that is being tested. Only one variable should be used

Control The experimenter makes a special effort to keep other factors constant so that they will not effect the outcome. Those factors are called control variables.

Other Variables The factor that is changed is known as the independent variable. The factor that is measured or observed is called the dependent variable.

DRY MIX DRY= Dependent, responds, plot on Y axis MIX= Manipulated, Independent, plot on X axis

Example of Controls & Variables For example, suppose you want to figure out the fastest route to walk home from school. You will try several different routes and time how long it takes you to get home by each one. Since you are only interested in finding a route that is fastest for you, you will do the walking yourself.

What are the Variables in Your Experiment? Varying the route is the independent variable The time it takes is the dependent variable Keeping the same walker throughout makes the walker a control variable.

Your Turn! Design an experiment where you are testing which brand of batteries lasts the longest. What is the INDEPENDENT Variable? What is the CONTROL?

Scientific Measurement Science uses the METRIC system System based on the unit 10 Length= Meters Mass= Grams Volume= Liters or Meters ²

Prefixes Milli=. 001 (thousandth) Centi=. 01 (hundredth) Deci=. 1 (tenth) Deka= 10 Hecto= 100 Kilo= 1000

Tools to Measure with Meter Stick for Length Triple Beam Balance for Mass Graduated Cylinder for Volume