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.