Scientific Method
Italian Physicist Galileo Galilei
English Philosopher Francis Bacon
*Credited as founders of the
Scientific Method
Step One: A question…
Experiments begin by posing a
Scientific Question.
Ex: If I add salt to water will it
affect its freezing temperature?
Should be simple with a yes or no
answer as an outcome.
Develop a Hypothesis..
A prediction about what will happen…
An Educated Guess…
*I predict that adding salt to the water
will make it take longer to freeze.
Design an Experiment
or test…
Design a test or series
of tests that will help
you determine if your
hypothesis is correct
or if it needs to be
modified.
Identify the Variables.
*Variable: a factor that can change.
*Manipulated Variable: a factor you
purposely change to look for an effect.
(added salt)
*Responding Variable: a factor that
changes as a result of the manipulation
of another variable. (freezing temp)
Controlling Variables
A well designed experiment…
*has controlled, identified variables.
*has only one variable manipulated
*has a responding variable you can
identify and measure.
Experimental Design
*Operational definitions
(Procedures): Steps & processes
which determine a result has taken
place/how to measure it.
Interpreting Data
Record the results of your
experiment.
Look for data (information) that
shows a change or a result.
Interpret the data to see what has
actually occurred.
Draw Conclusions
Summarize your results.
Does data support hypothesis?
Was hypothesis correct?
Did I ask the right question?
Conclusions can lead to new questions.